64631696220 has 576 divisors, whose sum is σ = 250967808000. Its totient is φ = 13095032832.

The previous prime is 64631696203. The next prime is 64631696267. The reversal of 64631696220 is 2269613646.

64631696220 is a `hidden beast` number, since 6 + 4 + 6 + 3 + 16 + 9 + 622 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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 191 ways as a sum of consecutive naturals, for example, 170531991 + ... + 170532369.

It is an arithmetic number, because the mean of its divisors is an integer number (435708000).

Almost surely, 2^64631696220 is an apocalyptic number.

64631696220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64631696220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125483904000).

64631696220 is an abundant number, since it is smaller than the sum of its proper divisors (186336111780).

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

64631696220 is a wasteful number, since it uses less digits than its factorization.

64631696220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 802 (or 797 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The spelling of 64631696220 in words is "sixty-four billion, six hundred thirty-one million, six hundred ninety-six thousand, two hundred twenty".