21182270957 has 2 divisors, whose sum is σ = 21182270958. Its totient is φ = 21182270956.

The previous prime is 21182270951. The next prime is 21182270987. The reversal of 21182270957 is 75907228112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21174324196 + 7946761 = 145514^2 + 2819^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21182270957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21182270951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10591135478 + 10591135479.

It is an arithmetic number, because the mean of its divisors is an integer number (10591135479).

Almost surely, 2^21182270957 is an apocalyptic number.

It is an amenable number.

21182270957 is a deficient number, since it is larger than the sum of its proper divisors (1).

21182270957 is an equidigital number, since it uses as much as digits as its factorization.

21182270957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 141120, while the sum is 44.

The spelling of 21182270957 in words is "twenty-one billion, one hundred eighty-two million, two hundred seventy thousand, nine hundred fifty-seven".