81275577820790 has 8 divisors (see below), whose sum is σ = 146296040077440. Its totient is φ = 32510231128312.

The previous prime is 81275577820753. The next prime is 81275577820807. The reversal of 81275577820790 is 9702877557218.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 81275577820790.

It is a congruent number.

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, 4063778891030 + ... + 4063778891049.

It is an arithmetic number, because the mean of its divisors is an integer number (18287005009680).

Almost surely, 2^{81275577820790} is an apocalyptic number.

81275577820790 is a deficient number, since it is larger than the sum of its proper divisors (65020462256650).

81275577820790 is a wasteful number, since it uses less digits than its factorization.

81275577820790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8127557782086.

The product of its (nonzero) digits is 138297600, while the sum is 68.

The spelling of 81275577820790 in words is "eighty-one trillion, two hundred seventy-five billion, five hundred seventy-seven million, eight hundred twenty thousand, seven hundred ninety".