20742885 has 20 divisors (see below), whose sum is σ = 37184268. Its totient is φ = 11062656.

The previous prime is 20742881. The next prime is 20742893. The reversal of 20742885 is 58824702.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7193124 + 13549761 = 2682^2 + 3681^2 .

It is not a de Polignac number, because 20742885 - 2² = 20742881 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20742881) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 25204 + ... + 26013.

Almost surely, 2^20742885 is an apocalyptic number.

It is an amenable number.

20742885 is a deficient number, since it is larger than the sum of its proper divisors (16441383).

20742885 is an equidigital number, since it uses as much as digits as its factorization.

20742885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51234 (or 51225 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The square root of 20742885 is about 4554.4357499036. The cubic root of 20742885 is about 274.7618213202.

The spelling of 20742885 in words is "twenty million, seven hundred forty-two thousand, eight hundred eighty-five".