66101520 has 40 divisors (see below), whose sum is σ = 204915456. Its totient is φ = 17627008.

The previous prime is 66101509. The next prime is 66101543. The reversal of 66101520 is 2510166.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

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, 137472 + ... + 137951.

Almost surely, 2^66101520 is an apocalyptic number.

66101520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66101520 is an abundant number, since it is smaller than the sum of its proper divisors (138813936).

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

66101520 is a wasteful number, since it uses less digits than its factorization.

66101520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275439 (or 275433 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 66101520 is about 8130.2841278765. The cubic root of 66101520 is about 404.3311013105.

Adding to 66101520 its reverse (2510166), we get a palindrome (68611686).

The spelling of 66101520 in words is "sixty-six million, one hundred one thousand, five hundred twenty".