20724403 has 32 divisors (see below), whose sum is σ = 26265600. Its totient is φ = 16299360.

The previous prime is 20724397. The next prime is 20724427. The reversal of 20724403 is 30442702.

It is not a de Polignac number, because 20724403 - 2⁵ = 20724371 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20724443) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 291858 + ... + 291928.

It is an arithmetic number, because the mean of its divisors is an integer number (820800).

Almost surely, 2^20724403 is an apocalyptic number.

20724403 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20724403 is a deficient number, since it is larger than the sum of its proper divisors (5541197).

20724403 is an equidigital number, since it uses as much as digits as its factorization.

20724403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 152 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 22.

The square root of 20724403 is about 4552.4062867894. The cubic root of 20724403 is about 274.6801924155.

The spelling of 20724403 in words is "twenty million, seven hundred twenty-four thousand, four hundred three".