31421818887 has 4 divisors (see below), whose sum is σ = 41895758520. Its totient is φ = 20947879256.

The previous prime is 31421818877. The next prime is 31421818927. The reversal of 31421818887 is 78881812413.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 31421818887 - 2²⁸ = 31153383431 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31421818837) 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, 5236969812 + ... + 5236969817.

It is an arithmetic number, because the mean of its divisors is an integer number (10473939630).

Almost surely, 2^31421818887 is an apocalyptic number.

31421818887 is a deficient number, since it is larger than the sum of its proper divisors (10473939633).

31421818887 is a wasteful number, since it uses less digits than its factorization.

31421818887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10473939632.

The product of its digits is 688128, while the sum is 51.

The spelling of 31421818887 in words is "thirty-one billion, four hundred twenty-one million, eight hundred eighteen thousand, eight hundred eighty-seven".