66121057357 has 16 divisors (see below), whose sum is σ = 67395811392. Its totient is φ = 64856937600.

The previous prime is 66121057283. The next prime is 66121057399. The reversal of 66121057357 is 75375012166.

It is not a de Polignac number, because 66121057357 - 2⁷ = 66121057229 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66121057157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21557338 + ... + 21560404.

It is an arithmetic number, because the mean of its divisors is an integer number (4212238212).

Almost surely, 2^66121057357 is an apocalyptic number.

It is an amenable number.

66121057357 is a deficient number, since it is larger than the sum of its proper divisors (1274754035).

66121057357 is a wasteful number, since it uses less digits than its factorization.

66121057357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4668.

The product of its (nonzero) digits is 264600, while the sum is 43.

The spelling of 66121057357 in words is "sixty-six billion, one hundred twenty-one million, fifty-seven thousand, three hundred fifty-seven".