61999505768 has 16 divisors (see below), whose sum is σ = 120257662500. Its totient is φ = 29930795776.

The previous prime is 61999505759. The next prime is 61999505819. The reversal of 61999505768 is 86750599916.

It can be written as a sum of positive squares in 2 ways, for example, as 60859903204 + 1139602564 = 246698^2 + 33758^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133619393 + ... + 133619856.

Almost surely, 2^61999505768 is an apocalyptic number.

It is an amenable number.

61999505768 is a deficient number, since it is larger than the sum of its proper divisors (58258156732).

61999505768 is a wasteful number, since it uses less digits than its factorization.

61999505768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267239284 (or 267239280 counting only the distinct ones).

The product of its (nonzero) digits is 36741600, while the sum is 65.

The spelling of 61999505768 in words is "sixty-one billion, nine hundred ninety-nine million, five hundred five thousand, seven hundred sixty-eight".