20624591 has 6 divisors (see below), whose sum is σ = 22333320. Its totient is φ = 19037928.

The previous prime is 20624581. The next prime is 20624603. The reversal of 20624591 is 19542602.

It is a happy number.

It is not a de Polignac number, because 20624591 - 2²² = 16430287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20624531) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 60851 + ... + 61188.

It is an arithmetic number, because the mean of its divisors is an integer number (3722220).

Almost surely, 2^20624591 is an apocalyptic number.

20624591 is a deficient number, since it is larger than the sum of its proper divisors (1708729).

20624591 is a wasteful number, since it uses less digits than its factorization.

20624591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122065 (or 122052 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 20624591 is about 4541.4305015050. The cubic root of 20624591 is about 274.2385148534.

The spelling of 20624591 in words is "twenty million, six hundred twenty-four thousand, five hundred ninety-one".