20973553 has 2 divisors, whose sum is σ = 20973554. Its totient is φ = 20973552.

The previous prime is 20973527. The next prime is 20973593. The reversal of 20973553 is 35537902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20866624 + 106929 = 4568^2 + 327^2 .

It is a cyclic number.

It is not a de Polignac number, because 20973553 - 2⁵ = 20973521 is a prime.

It is not a weakly prime, because it can be changed into another prime (20973523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10486776 + 10486777.

It is an arithmetic number, because the mean of its divisors is an integer number (10486777).

Almost surely, 2^20973553 is an apocalyptic number.

It is an amenable number.

20973553 is a deficient number, since it is larger than the sum of its proper divisors (1).

20973553 is an equidigital number, since it uses as much as digits as its factorization.

20973553 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28350, while the sum is 34.

The square root of 20973553 is about 4579.6891815930. The cubic root of 20973553 is about 275.7765510992.

The spelling of 20973553 in words is "twenty million, nine hundred seventy-three thousand, five hundred fifty-three".