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131021431 = 178878689
BaseRepresentation
bin1111100111100…
…11101001110111
3100010112120121121
413303303221313
5232020141211
621000124411
73150443452
oct763635167
9303476547
10131021431
1167a5a382
1237a66707
13211b5698
1413588499
15b781271
hex7cf3a77

131021431 has 8 divisors (see below), whose sum is σ = 138900960. Its totient is φ = 123161088.

The previous prime is 131021413. The next prime is 131021441. The reversal of 131021431 is 134120131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 131021431 - 25 = 131021399 is a prime.

It is a super-2 number, since 2×1310214312 = 34333230762575522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131021411) 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 7 ways as a sum of consecutive naturals, for example, 10735 + ... + 19423.

It is an arithmetic number, because the mean of its divisors is an integer number (17362620).

Almost surely, 2131021431 is an apocalyptic number.

131021431 is a deficient number, since it is larger than the sum of its proper divisors (7879529).

131021431 is an equidigital number, since it uses as much as digits as its factorization.

131021431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9593.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 131021431 is about 11446.4593215544. The cubic root of 131021431 is about 507.9030016612.

Adding to 131021431 its reverse (134120131), we get a palindrome (265141562).

The spelling of 131021431 in words is "one hundred thirty-one million, twenty-one thousand, four hundred thirty-one".

Divisors: 1 17 887 8689 15079 147713 7707143 131021431