665693730 has 96 divisors (see below), whose sum is σ = 1875654144. Its totient is φ = 162834048.

The previous prime is 665693713. The next prime is 665693773. The reversal of 665693730 is 37396566.

It is a super-2 number, since 2×665693730² = 886296284322625800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 193687 + ... + 197093.

It is an arithmetic number, because the mean of its divisors is an integer number (19538064).

Almost surely, 2^665693730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 665693730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (937827072).

665693730 is an abundant number, since it is smaller than the sum of its proper divisors (1209960414).

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

665693730 is a wasteful number, since it uses less digits than its factorization.

665693730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3600 (or 3597 counting only the distinct ones).

The product of its (nonzero) digits is 612360, while the sum is 45.

The square root of 665693730 is about 25801.0412580578. The cubic root of 665693730 is about 873.1552886017.

The spelling of 665693730 in words is "six hundred sixty-five million, six hundred ninety-three thousand, seven hundred thirty".