31809752893 has 4 divisors (see below), whose sum is σ = 31810868320. Its totient is φ = 31808637468.

The previous prime is 31809752879. The next prime is 31809752911. The reversal of 31809752893 is 39825790813.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39825790813 = 41843 ⋅951791.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31809752893 is a prime.

It is a super-2 number, since 2×31809752893² (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 (31809752393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 513783 + ... + 572356.

It is an arithmetic number, because the mean of its divisors is an integer number (7952717080).

Almost surely, 2^31809752893 is an apocalyptic number.

It is an amenable number.

31809752893 is a deficient number, since it is larger than the sum of its proper divisors (1115427).

31809752893 is a wasteful number, since it uses less digits than its factorization.

31809752893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1115426.

The product of its (nonzero) digits is 3265920, while the sum is 55.

The spelling of 31809752893 in words is "thirty-one billion, eight hundred nine million, seven hundred fifty-two thousand, eight hundred ninety-three".