66572557 has 16 divisors (see below), whose sum is σ = 72027648. Its totient is φ = 61372080.

The previous prime is 66572551. The next prime is 66572567. The reversal of 66572557 is 75527566.

It is a cyclic number.

It is not a de Polignac number, because 66572557 - 2²³ = 58183949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66572551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81682 + ... + 82492.

It is an arithmetic number, because the mean of its divisors is an integer number (4501728).

Almost surely, 2^66572557 is an apocalyptic number.

It is an amenable number.

66572557 is a deficient number, since it is larger than the sum of its proper divisors (5455091).

66572557 is a wasteful number, since it uses less digits than its factorization.

66572557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 960.

The product of its digits is 441000, while the sum is 43.

The square root of 66572557 is about 8159.2007574272. The cubic root of 66572557 is about 405.2892451873.

The spelling of 66572557 in words is "sixty-six million, five hundred seventy-two thousand, five hundred fifty-seven".