31428872888866 has 4 divisors (see below), whose sum is σ = 47143309333302. Its totient is φ = 15714436444432.

The previous prime is 31428872888807. The next prime is 31428872888867. The reversal of 31428872888866 is 66888827882413.

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

It can be written as a sum of positive squares in only one way, i.e., 28106167325625 + 3322705563241 = 5301525^2 + 1822829^2 .

It is not an unprimeable number, because it can be changed into a prime (31428872888867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7857218222215 + ... + 7857218222218.

Almost surely, 2^{31428872888866} is an apocalyptic number.

31428872888866 is a deficient number, since it is larger than the sum of its proper divisors (15714436444436).

31428872888866 is a wasteful number, since it uses less digits than its factorization.

31428872888866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15714436444435.

The product of its digits is 3170893824, while the sum is 79.

The spelling of 31428872888866 in words is "thirty-one trillion, four hundred twenty-eight billion, eight hundred seventy-two million, eight hundred eighty-eight thousand, eight hundred sixty-six".