28731507288866 has 16 divisors (see below), whose sum is σ = 44231969985120. Its totient is φ = 13992335591520.

The previous prime is 28731507288791. The next prime is 28731507288881. The reversal of 28731507288866 is 66888270513782.

It is a happy number.

It is a super-2 number, since 2×28731507288866² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28731507288866.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1204562420 + ... + 1204586271.

It is an arithmetic number, because the mean of its divisors is an integer number (2764498124070).

Almost surely, 2^{28731507288866} is an apocalyptic number.

28731507288866 is a deficient number, since it is larger than the sum of its proper divisors (15500462696254).

28731507288866 is a wasteful number, since it uses less digits than its factorization.

28731507288866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2409148849.

The product of its (nonzero) digits is 433520640, while the sum is 71.

The spelling of 28731507288866 in words is "twenty-eight trillion, seven hundred thirty-one billion, five hundred seven million, two hundred eighty-eight thousand, eight hundred sixty-six".