28776644964 has 18 divisors (see below), whose sum is σ = 72740963750. Its totient is φ = 9592214976.

The previous prime is 28776644951. The next prime is 28776644983. The reversal of 28776644964 is 46944667782.

28776644964 is a `hidden beast` number, since 2 + 8 + 77 + 66 + 449 + 64 = 666.

It can be written as a sum of positive squares in only one way, i.e., 18411776100 + 10364868864 = 135690^2 + 101808^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×28776644964² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 399675589 + ... + 399675660.

Almost surely, 2^28776644964 is an apocalyptic number.

It is an amenable number.

28776644964 is an abundant number, since it is smaller than the sum of its proper divisors (43964318786).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28776644964 is a wasteful number, since it uses less digits than its factorization.

28776644964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 799351259 (or 799351254 counting only the distinct ones).

The product of its digits is 97542144, while the sum is 63.

The spelling of 28776644964 in words is "twenty-eight billion, seven hundred seventy-six million, six hundred forty-four thousand, nine hundred sixty-four".