649666979856 has 60 divisors (see below), whose sum is σ = 1818544929708. Its totient is φ = 216510435072.

The previous prime is 649666979833. The next prime is 649666979869. The reversal of 649666979856 is 658979666946.

It can be written as a sum of positive squares in 2 ways, for example, as 344432829456 + 305234150400 = 586884^2 + 552480^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 224386 + ... + 1161758.

Almost surely, 2^649666979856 is an apocalyptic number.

It is an amenable number.

649666979856 is an abundant number, since it is smaller than the sum of its proper divisors (1168877949852).

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

649666979856 is a wasteful number, since it uses less digits than its factorization.

649666979856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 942200 (or 942191 counting only the distinct ones).

The product of its digits is 6348948480, while the sum is 81.

The spelling of 649666979856 in words is "six hundred forty-nine billion, six hundred sixty-six million, nine hundred seventy-nine thousand, eight hundred fifty-six".