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31223013213 = 373271454543
BaseRepresentation
bin11101000101000010…
…010101111101011101
32222120222121102002210
4131011002111331131
51002421042410323
622202121311033
72153510143020
oct350502257535
988528542083
1031223013213
1112272638a57
126074635479
132c37886362
141722a491b7
15c2b1ad293
hex745095f5d

31223013213 has 16 divisors (see below), whose sum is σ = 47592574976. Its totient is φ = 17836228080.

The previous prime is 31223013181. The next prime is 31223013223. The reversal of 31223013213 is 31231032213.

It is not a de Polignac number, because 31223013213 - 25 = 31223013181 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31223013213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31223013223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 158581 + ... + 295962.

It is an arithmetic number, because the mean of its divisors is an integer number (2974535936).

Almost surely, 231223013213 is an apocalyptic number.

It is an amenable number.

31223013213 is a deficient number, since it is larger than the sum of its proper divisors (16369561763).

31223013213 is a wasteful number, since it uses less digits than its factorization.

31223013213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457824.

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 31223013213 its reverse (31231032213), we get a palindrome (62454045426).

The spelling of 31223013213 in words is "thirty-one billion, two hundred twenty-three million, thirteen thousand, two hundred thirteen".

Divisors: 1 3 7 21 3271 9813 22897 68691 454543 1363629 3181801 9545403 1486810153 4460430459 10407671071 31223013213