20957479 has 2 divisors, whose sum is σ = 20957480. Its totient is φ = 20957478.

The previous prime is 20957473. The next prime is 20957491. The reversal of 20957479 is 97475902.

20957479 is nontrivially palindromic in base 12.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20957479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20957473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10478739 + 10478740.

It is an arithmetic number, because the mean of its divisors is an integer number (10478740).

Almost surely, 2^20957479 is an apocalyptic number.

20957479 is a deficient number, since it is larger than the sum of its proper divisors (1).

20957479 is an equidigital number, since it uses as much as digits as its factorization.

20957479 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 158760, while the sum is 43.

The square root of 20957479 is about 4577.9339226337. The cubic root of 20957479 is about 275.7060819518.

The spelling of 20957479 in words is "twenty million, nine hundred fifty-seven thousand, four hundred seventy-nine".