20742475 has 12 divisors (see below), whose sum is σ = 27699616. Its totient is φ = 15317280.

The previous prime is 20742461. The next prime is 20742479. The reversal of 20742475 is 57424702.

It is not a de Polignac number, because 20742475 - 2⁵ = 20742443 is a prime.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20742479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31587 + ... + 32236.

Almost surely, 2^20742475 is an apocalyptic number.

20742475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20742475 is a deficient number, since it is larger than the sum of its proper divisors (6957141).

20742475 is a wasteful number, since it uses less digits than its factorization.

20742475 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63846 (or 63841 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 31.

The square root of 20742475 is about 4554.3907386170. The cubic root of 20742475 is about 274.7600110113.

The spelling of 20742475 in words is "twenty million, seven hundred forty-two thousand, four hundred seventy-five".