21312099983 has 2 divisors, whose sum is σ = 21312099984. Its totient is φ = 21312099982.

The previous prime is 21312099973. The next prime is 21312100021. The reversal of 21312099983 is 38999021312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21312099983 - 2⁴ = 21312099967 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21312099973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10656049991 + 10656049992.

It is an arithmetic number, because the mean of its divisors is an integer number (10656049992).

Almost surely, 2^21312099983 is an apocalyptic number.

21312099983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21312099983 is an equidigital number, since it uses as much as digits as its factorization.

21312099983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 209952, while the sum is 47.

The spelling of 21312099983 in words is "twenty-one billion, three hundred twelve million, ninety-nine thousand, nine hundred eighty-three".