20261957 has 4 divisors (see below), whose sum is σ = 20605440. Its totient is φ = 19918476.

The previous prime is 20261947. The next prime is 20261959. The reversal of 20261957 is 75916202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20261957 - 2⁸ = 20261701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20261959) 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 3 ways as a sum of consecutive naturals, for example, 171653 + ... + 171770.

It is an arithmetic number, because the mean of its divisors is an integer number (5151360).

Almost surely, 2^20261957 is an apocalyptic number.

It is an amenable number.

20261957 is a deficient number, since it is larger than the sum of its proper divisors (343483).

20261957 is an equidigital number, since it uses as much as digits as its factorization.

20261957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 343482.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 20261957 is about 4501.3283594957. The cubic root of 20261957 is about 272.6217260505.

It can be divided in two parts, 2026195 and 7, that added together give a palindrome (2026202).

The spelling of 20261957 in words is "twenty million, two hundred sixty-one thousand, nine hundred fifty-seven".