15642323491 has 4 divisors (see below), whose sum is σ = 15665226552. Its totient is φ = 15619420432.

The previous prime is 15642323467. The next prime is 15642323497. The reversal of 15642323491 is 19432324651.

15642323491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19432324651 = 19 ⋅1022753929.

It is a cyclic number.

It is not a de Polignac number, because 15642323491 - 2¹⁵ = 15642290723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15642323497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11450506 + ... + 11451871.

It is an arithmetic number, because the mean of its divisors is an integer number (3916306638).

Almost surely, 2^15642323491 is an apocalyptic number.

15642323491 is a deficient number, since it is larger than the sum of its proper divisors (22903061).

15642323491 is an equidigital number, since it uses as much as digits as its factorization.

15642323491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22903060.

The product of its digits is 155520, while the sum is 40.

The spelling of 15642323491 in words is "fifteen billion, six hundred forty-two million, three hundred twenty-three thousand, four hundred ninety-one".