15540451431 has 8 divisors (see below), whose sum is σ = 20721177840. Its totient is φ = 10360012992.

The previous prime is 15540451391. The next prime is 15540451453. The reversal of 15540451431 is 13415404551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15540451431 - 2¹⁷ = 15540320359 is a prime.

It is a super-2 number, since 2×15540451431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 15540451392 and 15540451401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15540451471) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 174385 + ... + 247973.

It is an arithmetic number, because the mean of its divisors is an integer number (2590147230).

Almost surely, 2^15540451431 is an apocalyptic number.

15540451431 is a deficient number, since it is larger than the sum of its proper divisors (5180726409).

15540451431 is an equidigital number, since it uses as much as digits as its factorization.

15540451431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143985.

The product of its (nonzero) digits is 24000, while the sum is 33.

Adding to 15540451431 its reverse (13415404551), we get a palindrome (28955855982).

The spelling of 15540451431 in words is "fifteen billion, five hundred forty million, four hundred fifty-one thousand, four hundred thirty-one".