81386762390 has 32 divisors (see below), whose sum is σ = 154483549920. Its totient is φ = 30785889024.

The previous prime is 81386762357. The next prime is 81386762393. The reversal of 81386762390 is 9326768318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81386762393) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278687 + ... + 490346.

It is an arithmetic number, because the mean of its divisors is an integer number (4827610935).

Almost surely, 2^81386762390 is an apocalyptic number.

81386762390 is a deficient number, since it is larger than the sum of its proper divisors (73096787530).

81386762390 is a wasteful number, since it uses less digits than its factorization.

81386762390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769616.

The product of its (nonzero) digits is 2612736, while the sum is 53.

The spelling of 81386762390 in words is "eighty-one billion, three hundred eighty-six million, seven hundred sixty-two thousand, three hundred ninety".