21113332957 has 2 divisors, whose sum is σ = 21113332958. Its totient is φ = 21113332956.

The previous prime is 21113332909. The next prime is 21113333009. The reversal of 21113332957 is 75923331112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12891558681 + 8221774276 = 113541^2 + 90674^2 .

It is a cyclic number.

It is not a de Polignac number, because 21113332957 - 2¹⁵ = 21113300189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21113336957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556666478 + 10556666479.

It is an arithmetic number, because the mean of its divisors is an integer number (10556666479).

Almost surely, 2^21113332957 is an apocalyptic number.

It is an amenable number.

21113332957 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113332957 is an equidigital number, since it uses as much as digits as its factorization.

21113332957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34020, while the sum is 37.

The spelling of 21113332957 in words is "twenty-one billion, one hundred thirteen million, three hundred thirty-two thousand, nine hundred fifty-seven".