31213354431 has 16 divisors (see below), whose sum is σ = 49097504768. Its totient is φ = 17260840800.

The previous prime is 31213354429. The next prime is 31213354499. The reversal of 31213354431 is 13445331213.

It is a happy number.

It is not a de Polignac number, because 31213354431 - 2¹ = 31213354429 is a prime.

It is a super-2 number, since 2×31213354431² (a number of 22 digits) 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 (31213354421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23972740 + ... + 23974041.

It is an arithmetic number, because the mean of its divisors is an integer number (3068594048).

Almost surely, 2^31213354431 is an apocalyptic number.

31213354431 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

31213354431 is a deficient number, since it is larger than the sum of its proper divisors (17884150337).

31213354431 is a wasteful number, since it uses less digits than its factorization.

31213354431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47946822.

The product of its digits is 12960, while the sum is 30.

Adding to 31213354431 its reverse (13445331213), we get a palindrome (44658685644).

The spelling of 31213354431 in words is "thirty-one billion, two hundred thirteen million, three hundred fifty-four thousand, four hundred thirty-one".