20957653 has 2 divisors, whose sum is σ = 20957654. Its totient is φ = 20957652.

The previous prime is 20957621. The next prime is 20957659. The reversal of 20957653 is 35675902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19377604 + 1580049 = 4402^2 + 1257^2 .

It is a cyclic number.

It is not a de Polignac number, because 20957653 - 2⁵ = 20957621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20957659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10478826 + 10478827.

It is an arithmetic number, because the mean of its divisors is an integer number (10478827).

Almost surely, 2^20957653 is an apocalyptic number.

It is an amenable number.

20957653 is a deficient number, since it is larger than the sum of its proper divisors (1).

20957653 is an equidigital number, since it uses as much as digits as its factorization.

20957653 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56700, while the sum is 37.

The square root of 20957653 is about 4577.9529268004. The cubic root of 20957653 is about 275.7068449686.

The spelling of 20957653 in words is "twenty million, nine hundred fifty-seven thousand, six hundred fifty-three".