21213220310939 has 2 divisors, whose sum is σ = 21213220310940. Its totient is φ = 21213220310938.

The previous prime is 21213220310929. The next prime is 21213220310957. The reversal of 21213220310939 is 93901302231212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21213220310939 - 2¹⁶ = 21213220245403 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21213220310929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606610155469 + 10606610155470.

It is an arithmetic number, because the mean of its divisors is an integer number (10606610155470).

Almost surely, 2^{21213220310939} is an apocalyptic number.

21213220310939 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213220310939 is an equidigital number, since it uses as much as digits as its factorization.

21213220310939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 38.

The spelling of 21213220310939 in words is "twenty-one trillion, two hundred thirteen billion, two hundred twenty million, three hundred ten thousand, nine hundred thirty-nine".