15640156401 has 4 divisors (see below), whose sum is σ = 20853541872. Its totient is φ = 10426770932.

The previous prime is 15640156397. The next prime is 15640156421. The reversal of 15640156401 is 10465104651.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 15640156401 - 2² = 15640156397 is a prime.

It is a super-2 number, since 2×15640156401² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (15640156421) 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, 2606692731 + ... + 2606692736.

It is an arithmetic number, because the mean of its divisors is an integer number (5213385468).

Almost surely, 2^15640156401 is an apocalyptic number.

It is an amenable number.

15640156401 is a deficient number, since it is larger than the sum of its proper divisors (5213385471).

15640156401 is an equidigital number, since it uses as much as digits as its factorization.

15640156401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5213385470.

The product of its (nonzero) digits is 14400, while the sum is 33.

The spelling of 15640156401 in words is "fifteen billion, six hundred forty million, one hundred fifty-six thousand, four hundred one".