31256201161 has 4 divisors (see below), whose sum is σ = 32901264400. Its totient is φ = 29611137924.

The previous prime is 31256201153. The next prime is 31256201177. The reversal of 31256201161 is 16110265213.

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.

It is a cyclic number.

It is not a de Polignac number, because 31256201161 - 2³ = 31256201153 is a prime.

It is a super-2 number, since 2×31256201161² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31256201101) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 822531591 + ... + 822531628.

It is an arithmetic number, because the mean of its divisors is an integer number (8225316100).

Almost surely, 2^31256201161 is an apocalyptic number.

It is an amenable number.

31256201161 is a deficient number, since it is larger than the sum of its proper divisors (1645063239).

31256201161 is a wasteful number, since it uses less digits than its factorization.

31256201161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1645063238.

The product of its (nonzero) digits is 2160, while the sum is 28.

Adding to 31256201161 its reverse (16110265213), we get a palindrome (47366466374).

The spelling of 31256201161 in words is "thirty-one billion, two hundred fifty-six million, two hundred one thousand, one hundred sixty-one".