21054697 has 2 divisors, whose sum is σ = 21054698. Its totient is φ = 21054696.

The previous prime is 21054661. The next prime is 21054703. The reversal of 21054697 is 79645012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20939776 + 114921 = 4576^2 + 339^2 .

It is a cyclic number.

It is not a de Polignac number, because 21054697 - 2⁷ = 21054569 is a prime.

It is not a weakly prime, because it can be changed into another prime (21054617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10527348 + 10527349.

It is an arithmetic number, because the mean of its divisors is an integer number (10527349).

Almost surely, 2^21054697 is an apocalyptic number.

It is an amenable number.

21054697 is a deficient number, since it is larger than the sum of its proper divisors (1).

21054697 is an equidigital number, since it uses as much as digits as its factorization.

21054697 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 21054697 is about 4588.5397459323. The cubic root of 21054697 is about 276.1317415244.

The spelling of 21054697 in words is "twenty-one million, fifty-four thousand, six hundred ninety-seven".