15432438991 has 18 divisors (see below), whose sum is σ = 16031674176. Its totient is φ = 14855349600.

The previous prime is 15432438977. The next prime is 15432439069. The reversal of 15432438991 is 19983423451.

It is not a de Polignac number, because 15432438991 - 2³³ = 6842504399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15432438971) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 10490386 + ... + 10491856.

Almost surely, 2^15432438991 is an apocalyptic number.

15432438991 is a deficient number, since it is larger than the sum of its proper divisors (599235185).

15432438991 is an frugal number, since it uses more digits than its factorization.

15432438991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1711 (or 1591 counting only the distinct ones).

The product of its digits is 933120, while the sum is 49.

The spelling of 15432438991 in words is "fifteen billion, four hundred thirty-two million, four hundred thirty-eight thousand, nine hundred ninety-one".