64171987722 has 56 divisors (see below), whose sum is σ = 151916856960. Its totient is φ = 20264829480.

The previous prime is 64171987717. The next prime is 64171987769. The reversal of 64171987722 is 22778917146.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 1130554 + ... + 1185957.

Almost surely, 2^64171987722 is an apocalyptic number.

64171987722 is an abundant number, since it is smaller than the sum of its proper divisors (87744869238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64171987722 is a wasteful number, since it uses less digits than its factorization.

64171987722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2316550 (or 2316535 counting only the distinct ones).

The product of its digits is 2370816, while the sum is 54.

The spelling of 64171987722 in words is "sixty-four billion, one hundred seventy-one million, nine hundred eighty-seven thousand, seven hundred twenty-two".