20919520 has 48 divisors (see below), whose sum is σ = 52336368. Its totient is φ = 7874560.

The previous prime is 20919517. The next prime is 20919533. The reversal of 20919520 is 2591902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1126 + ... + 6565.

It is an arithmetic number, because the mean of its divisors is an integer number (1090341).

Almost surely, 2^20919520 is an apocalyptic number.

20919520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20919520 is an abundant number, since it is smaller than the sum of its proper divisors (31416848).

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

20919520 is a wasteful number, since it uses less digits than its factorization.

20919520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7723 (or 7715 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 20919520 is about 4573.7861777744. The cubic root of 20919520 is about 275.5395248315.

It can be divided in two parts, 2091 and 9520, that added together give a palindrome (11611).

The spelling of 20919520 in words is "twenty million, nine hundred nineteen thousand, five hundred twenty".