81541717530 has 96 divisors (see below), whose sum is σ = 242185209984. Its totient is φ = 17204398848.

The previous prime is 81541717519. The next prime is 81541717547. The reversal of 81541717530 is 3571714518.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1113309 + ... + 1184288.

It is an arithmetic number, because the mean of its divisors is an integer number (2522762604).

Almost surely, 2^81541717530 is an apocalyptic number.

81541717530 is an abundant number, since it is smaller than the sum of its proper divisors (160643492454).

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

81541717530 is a wasteful number, since it uses less digits than its factorization.

81541717530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2297640 (or 2297627 counting only the distinct ones).

The product of its (nonzero) digits is 117600, while the sum is 42.

The spelling of 81541717530 in words is "eighty-one billion, five hundred forty-one million, seven hundred seventeen thousand, five hundred thirty".