64101615981 has 16 divisors (see below), whose sum is σ = 97457661504. Its totient is φ = 37126727424.

The previous prime is 64101615971. The next prime is 64101615989. The reversal of 64101615981 is 18951610146.

It is a happy number.

64101615981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 64101615981 - 2¹⁰ = 64101614957 is a prime.

It is a super-2 number, since 2×64101615981² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64101615989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48341431 + ... + 48342756.

It is an arithmetic number, because the mean of its divisors is an integer number (6091103844).

Almost surely, 2^64101615981 is an apocalyptic number.

It is an amenable number.

64101615981 is a deficient number, since it is larger than the sum of its proper divisors (33356045523).

64101615981 is a wasteful number, since it uses less digits than its factorization.

64101615981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96684220.

The product of its (nonzero) digits is 51840, while the sum is 42.

The spelling of 64101615981 in words is "sixty-four billion, one hundred one million, six hundred fifteen thousand, nine hundred eighty-one".