81635430 has 32 divisors (see below), whose sum is σ = 196291584. Its totient is φ = 21728736.

The previous prime is 81635429. The next prime is 81635459. The reversal of 81635430 is 3453618.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15969 + ... + 20451.

It is an arithmetic number, because the mean of its divisors is an integer number (6134112).

Almost surely, 2^81635430 is an apocalyptic number.

81635430 is an abundant number, since it is smaller than the sum of its proper divisors (114656154).

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

81635430 is a wasteful number, since it uses less digits than its factorization.

81635430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5100.

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 81635430 is about 9035.2327031461. The cubic root of 81635430 is about 433.8033434105.

The spelling of 81635430 in words is "eighty-one million, six hundred thirty-five thousand, four hundred thirty".