20920961953 has 2 divisors, whose sum is σ = 20920961954. Its totient is φ = 20920961952.

The previous prime is 20920961951. The next prime is 20920961977. The reversal of 20920961953 is 35916902902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20611483489 + 309478464 = 143567^2 + 17592^2 .

It is a cyclic number.

It is not a de Polignac number, because 20920961953 - 2¹ = 20920961951 is a prime.

Together with 20920961951, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20920961951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10460480976 + 10460480977.

It is an arithmetic number, because the mean of its divisors is an integer number (10460480977).

Almost surely, 2^20920961953 is an apocalyptic number.

It is an amenable number.

20920961953 is a deficient number, since it is larger than the sum of its proper divisors (1).

20920961953 is an equidigital number, since it uses as much as digits as its factorization.

20920961953 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 262440, while the sum is 46.

The spelling of 20920961953 in words is "twenty billion, nine hundred twenty million, nine hundred sixty-one thousand, nine hundred fifty-three".