66121875 has 36 divisors (see below), whose sum is σ = 119429856. Its totient is φ = 35250000.

The previous prime is 66121873. The next prime is 66121877. The reversal of 66121875 is 57812166.

It is an interprime number because it is at equal distance from previous prime (66121873) and next prime (66121877).

It is not a de Polignac number, because 66121875 - 2¹ = 66121873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66121871) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 26950 + ... + 29300.

It is an arithmetic number, because the mean of its divisors is an integer number (3317496).

Almost surely, 2^66121875 is an apocalyptic number.

66121875 is a deficient number, since it is larger than the sum of its proper divisors (53307981).

66121875 is an equidigital number, since it uses as much as digits as its factorization.

66121875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2382 (or 2359 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 66121875 is about 8131.5358327932. The cubic root of 66121875 is about 404.3725996750.

It can be divided in two parts, 66121 and 875, that multiplied together give a palindrome (57855875).

The spelling of 66121875 in words is "sixty-six million, one hundred twenty-one thousand, eight hundred seventy-five".