81624630 has 16 divisors (see below), whose sum is σ = 195899184. Its totient is φ = 21766560.

The previous prime is 81624623. The next prime is 81624637. The reversal of 81624630 is 3642618.

It is an interprime number because it is at equal distance from previous prime (81624623) and next prime (81624637).

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 2720821 = 81624630 / (8 + 1 + 6 + 2 + 4 + 6 + 3 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81624637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1360381 + ... + 1360440.

It is an arithmetic number, because the mean of its divisors is an integer number (12243699).

Almost surely, 2^81624630 is an apocalyptic number.

81624630 is an abundant number, since it is smaller than the sum of its proper divisors (114274554).

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

81624630 is a wasteful number, since it uses less digits than its factorization.

81624630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2720831.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 81624630 is about 9034.6350230654. The cubic root of 81624630 is about 433.7842124902.

The spelling of 81624630 in words is "eighty-one million, six hundred twenty-four thousand, six hundred thirty".