66121025 has 12 divisors (see below), whose sum is σ = 83030400. Its totient is φ = 52225680.

The previous prime is 66120959. The next prime is 66121031. The reversal of 66121025 is 52012166.

It is not a de Polignac number, because 66121025 - 2¹⁰ = 66120001 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14765 + ... + 18714.

It is an arithmetic number, because the mean of its divisors is an integer number (6919200).

Almost surely, 2^66121025 is an apocalyptic number.

It is an amenable number.

66121025 is a deficient number, since it is larger than the sum of its proper divisors (16909375).

66121025 is a wasteful number, since it uses less digits than its factorization.

66121025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33568 (or 33563 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 66121025 is about 8131.4835669760. The cubic root of 66121025 is about 404.3708669243.

The spelling of 66121025 in words is "sixty-six million, one hundred twenty-one thousand, twenty-five".