21101302993 has 2 divisors, whose sum is σ = 21101302994. Its totient is φ = 21101302992.

The previous prime is 21101302969. The next prime is 21101302997. The reversal of 21101302993 is 39920310112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14818679824 + 6282623169 = 121732^2 + 79263^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101302993 is a prime.

It is not a weakly prime, because it can be changed into another prime (21101302997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550651496 + 10550651497.

It is an arithmetic number, because the mean of its divisors is an integer number (10550651497).

Almost surely, 2^21101302993 is an apocalyptic number.

It is an amenable number.

21101302993 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101302993 is an equidigital number, since it uses as much as digits as its factorization.

21101302993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 31.

The spelling of 21101302993 in words is "twenty-one billion, one hundred one million, three hundred two thousand, nine hundred ninety-three".