64646172272 has 80 divisors (see below), whose sum is σ = 145648044000. Its totient is φ = 27470315520.

The previous prime is 64646172271. The next prime is 64646172287. The reversal of 64646172272 is 27227164646.

64646172272 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×64646172272² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64646172271) 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, 373304 + ... + 518312.

It is an arithmetic number, because the mean of its divisors is an integer number (1820600550).

Almost surely, 2^64646172272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64646172272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72824022000).

64646172272 is an abundant number, since it is smaller than the sum of its proper divisors (81001871728).

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

64646172272 is a wasteful number, since it uses less digits than its factorization.

64646172272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145194 (or 145188 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 47.

The spelling of 64646172272 in words is "sixty-four billion, six hundred forty-six million, one hundred seventy-two thousand, two hundred seventy-two".