15640436881 has 8 divisors (see below), whose sum is σ = 15721548480. Its totient is φ = 15559432848.

The previous prime is 15640436873. The next prime is 15640436897. The reversal of 15640436881 is 18863404651.

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

It is a cyclic number.

It is not a de Polignac number, because 15640436881 - 2³ = 15640436873 is a prime.

It is a super-2 number, since 2×15640436881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15640436081) 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, 273295 + ... + 325531.

It is an arithmetic number, because the mean of its divisors is an integer number (1965193560).

Almost surely, 2^15640436881 is an apocalyptic number.

It is an amenable number.

15640436881 is a deficient number, since it is larger than the sum of its proper divisors (81111599).

15640436881 is a wasteful number, since it uses less digits than its factorization.

15640436881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53783.

The product of its (nonzero) digits is 552960, while the sum is 46.

The spelling of 15640436881 in words is "fifteen billion, six hundred forty million, four hundred thirty-six thousand, eight hundred eighty-one".