81764883650 has 24 divisors (see below), whose sum is σ = 152145316020. Its totient is φ = 32692484160.

The previous prime is 81764883619. The next prime is 81764883659. The reversal of 81764883650 is 5638846718.

It can be written as a sum of positive squares in 6 ways, for example, as 63549872281 + 18215011369 = 252091^2 + 134963^2 .

It is not an unprimeable number, because it can be changed into a prime (81764883659) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 213665 + ... + 457364.

Almost surely, 2^81764883650 is an apocalyptic number.

81764883650 is a deficient number, since it is larger than the sum of its proper divisors (70380432370).

81764883650 is a wasteful number, since it uses less digits than its factorization.

81764883650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673478 (or 673473 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 56.

The spelling of 81764883650 in words is "eighty-one billion, seven hundred sixty-four million, eight hundred eighty-three thousand, six hundred fifty".