665655501 has 32 divisors (see below), whose sum is σ = 1049149440. Its totient is φ = 367526016.

The previous prime is 665655499. The next prime is 665655503. The reversal of 665655501 is 105556566.

It is an interprime number because it is at equal distance from previous prime (665655499) and next prime (665655503).

It is not a de Polignac number, because 665655501 - 2¹ = 665655499 is a prime.

It is a super-2 number, since 2×665655501² = 886194492023122002, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 665655501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665655503) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 73705 + ... + 82241.

It is an arithmetic number, because the mean of its divisors is an integer number (32785920).

Almost surely, 2^665655501 is an apocalyptic number.

It is an amenable number.

665655501 is a deficient number, since it is larger than the sum of its proper divisors (383493939).

665655501 is a wasteful number, since it uses less digits than its factorization.

665655501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8673.

The product of its (nonzero) digits is 135000, while the sum is 39.

The square root of 665655501 is about 25800.3004052278. The cubic root of 665655501 is about 873.1385739620.

The spelling of 665655501 in words is "six hundred sixty-five million, six hundred fifty-five thousand, five hundred one".