15794400421 has 2 divisors, whose sum is σ = 15794400422. Its totient is φ = 15794400420.

The previous prime is 15794400407. The next prime is 15794400451. The reversal of 15794400421 is 12400449751.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14151719521 + 1642680900 = 118961^2 + 40530^2 .

It is a cyclic number.

It is not a de Polignac number, because 15794400421 - 2²¹ = 15792303269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15794400451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7897200210 + 7897200211.

It is an arithmetic number, because the mean of its divisors is an integer number (7897200211).

Almost surely, 2^15794400421 is an apocalyptic number.

It is an amenable number.

15794400421 is a deficient number, since it is larger than the sum of its proper divisors (1).

15794400421 is an equidigital number, since it uses as much as digits as its factorization.

15794400421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40320, while the sum is 37.

The spelling of 15794400421 in words is "fifteen billion, seven hundred ninety-four million, four hundred thousand, four hundred twenty-one".