15640093331 has 4 divisors (see below), whose sum is σ = 16021559064. Its totient is φ = 15258627600.

The previous prime is 15640093289. The next prime is 15640093351. The reversal of 15640093331 is 13339004651.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15640093331 is a prime.

It is a super-2 number, since 2×15640093331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15640093291 and 15640093300.

It is not an unprimeable number, because it can be changed into a prime (15640093351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190732805 + ... + 190732886.

It is an arithmetic number, because the mean of its divisors is an integer number (4005389766).

Almost surely, 2^15640093331 is an apocalyptic number.

15640093331 is a deficient number, since it is larger than the sum of its proper divisors (381465733).

15640093331 is an equidigital number, since it uses as much as digits as its factorization.

15640093331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381465732.

The product of its (nonzero) digits is 29160, while the sum is 35.

Adding to 15640093331 its reverse (13339004651), we get a palindrome (28979097982).

The spelling of 15640093331 in words is "fifteen billion, six hundred forty million, ninety-three thousand, three hundred thirty-one".