64991052 has 72 divisors (see below), whose sum is σ = 196020720. Its totient is φ = 18567360.

The previous prime is 64991029. The next prime is 64991053. The reversal of 64991052 is 25019946.

64991052 is a `hidden beast` number, since 649 + 9 + 1 + 0 + 5 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 64990998 and 64991016.

It is not an unprimeable number, because it can be changed into a prime (64991053) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 849 + ... + 11432.

It is an arithmetic number, because the mean of its divisors is an integer number (2722510).

Almost surely, 2^64991052 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 64991052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98010360).

64991052 is an abundant number, since it is smaller than the sum of its proper divisors (131029668).

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

64991052 is a wasteful number, since it uses less digits than its factorization.

64991052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12308 (or 12293 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 64991052 is about 8061.7027977965. The cubic root of 64991052 is about 402.0541250358.

The spelling of 64991052 in words is "sixty-four million, nine hundred ninety-one thousand, fifty-two".