75521281864 has 64 divisors (see below), whose sum is σ = 164881319040. Its totient is φ = 31761945600.

The previous prime is 75521281859. The next prime is 75521281867. The reversal of 75521281864 is 46818212557.

It is not an unprimeable number, because it can be changed into a prime (75521281867) 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, 580047 + ... + 698209.

It is an arithmetic number, because the mean of its divisors is an integer number (2576270610).

Almost surely, 2^75521281864 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 75521281864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82440659520).

75521281864 is an abundant number, since it is smaller than the sum of its proper divisors (89360037176).

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

75521281864 is a wasteful number, since it uses less digits than its factorization.

75521281864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118390 (or 118386 counting only the distinct ones).

The product of its digits is 1075200, while the sum is 49.

The spelling of 75521281864 in words is "seventy-five billion, five hundred twenty-one million, two hundred eighty-one thousand, eight hundred sixty-four".