31368261881 has 4 divisors (see below), whose sum is σ = 34219922064. Its totient is φ = 28516601700.

The previous prime is 31368261877. The next prime is 31368261901. The reversal of 31368261881 is 18816286313.

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 31368261881 - 2² = 31368261877 is a prime.

It is a super-2 number, since 2×31368261881² (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 (31368261851) 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, 1425830075 + ... + 1425830096.

It is an arithmetic number, because the mean of its divisors is an integer number (8554980516).

Almost surely, 2^31368261881 is an apocalyptic number.

It is an amenable number.

31368261881 is a deficient number, since it is larger than the sum of its proper divisors (2851660183).

31368261881 is a wasteful number, since it uses less digits than its factorization.

31368261881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2851660182.

The product of its digits is 331776, while the sum is 47.

The spelling of 31368261881 in words is "thirty-one billion, three hundred sixty-eight million, two hundred sixty-one thousand, eight hundred eighty-one".