64021997252 has 24 divisors (see below), whose sum is σ = 112692816600. Its totient is φ = 31824161280.

The previous prime is 64021997239. The next prime is 64021997269. The reversal of 64021997252 is 25279912046.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2723169856 + 61298827396 = 52184^2 + 247586^2 .

It is a super-2 number, since 2×64021997252² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 64021997197 and 64021997206.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2650124 + ... + 2674172.

It is an arithmetic number, because the mean of its divisors is an integer number (4695534025).

Almost surely, 2^64021997252 is an apocalyptic number.

It is an amenable number.

64021997252 is a deficient number, since it is larger than the sum of its proper divisors (48670819348).

64021997252 is a wasteful number, since it uses less digits than its factorization.

64021997252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27911 (or 27909 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 47.

The spelling of 64021997252 in words is "sixty-four billion, twenty-one million, nine hundred ninety-seven thousand, two hundred fifty-two".