20961504 has 60 divisors (see below), whose sum is σ = 61654824. Its totient is φ = 6986304.

The previous prime is 20961467. The next prime is 20961517. The reversal of 20961504 is 40516902.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1452 + ... + 6635.

Almost surely, 2^20961504 is an apocalyptic number.

20961504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

20961504 is an abundant number, since it is smaller than the sum of its proper divisors (40693320).

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

20961504 is an equidigital number, since it uses as much as digits as its factorization.

20961504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8109 (or 8092 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 20961504 is about 4578.3735103200. The cubic root of 20961504 is about 275.7237311157.

It can be divided in two parts, 2096 and 1504, that added together give a square (3600 = 60²).

The spelling of 20961504 in words is "twenty million, nine hundred sixty-one thousand, five hundred four".