665515720002 has 64 divisors (see below), whose sum is σ = 1602552453120. Its totient is φ = 179992036224.

The previous prime is 665515719997. The next prime is 665515720013. The reversal of 665515720002 is 200027515566.

It is a super-2 number, since 2×665515720002² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 634998 + ... + 1316910.

It is an arithmetic number, because the mean of its divisors is an integer number (25039882080).

Almost surely, 2^665515720002 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665515720002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (801276226560).

665515720002 is an abundant number, since it is smaller than the sum of its proper divisors (937036733118).

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

665515720002 is a wasteful number, since it uses less digits than its factorization.

665515720002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 683167.

The product of its (nonzero) digits is 126000, while the sum is 39.

The spelling of 665515720002 in words is "six hundred sixty-five billion, five hundred fifteen million, seven hundred twenty thousand, two".