21439257198433 has 2 divisors, whose sum is σ = 21439257198434. Its totient is φ = 21439257198432.

The previous prime is 21439257198389. The next prime is 21439257198451. The reversal of 21439257198433 is 33489175293412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18191649537889 + 3247607660544 = 4265167^2 + 1802112^2 .

It is a cyclic number.

It is not a de Polignac number, because 21439257198433 - 2²⁵ = 21439223644001 is a prime.

It is a super-2 number, since 2×21439257198433² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21439257198133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10719628599216 + 10719628599217.

It is an arithmetic number, because the mean of its divisors is an integer number (10719628599217).

Almost surely, 2^{21439257198433} is an apocalyptic number.

It is an amenable number.

21439257198433 is a deficient number, since it is larger than the sum of its proper divisors (1).

21439257198433 is an equidigital number, since it uses as much as digits as its factorization.

21439257198433 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39191040, while the sum is 61.

The spelling of 21439257198433 in words is "twenty-one trillion, four hundred thirty-nine billion, two hundred fifty-seven million, one hundred ninety-eight thousand, four hundred thirty-three".