66534257 has 8 divisors (see below), whose sum is σ = 70392000. Its totient is φ = 62712144.

The previous prime is 66534253. The next prime is 66534269. The reversal of 66534257 is 75243566.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66534257 - 2² = 66534253 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66534257.

It is not an unprimeable number, because it can be changed into a prime (66534253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5018 + ... + 12579.

It is an arithmetic number, because the mean of its divisors is an integer number (8799000).

Almost surely, 2^66534257 is an apocalyptic number.

It is an amenable number.

66534257 is a deficient number, since it is larger than the sum of its proper divisors (3857743).

66534257 is a wasteful number, since it uses less digits than its factorization.

66534257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17815.

The product of its digits is 151200, while the sum is 38.

The square root of 66534257 is about 8156.8533761494. The cubic root of 66534257 is about 405.2115076704.

The spelling of 66534257 in words is "sixty-six million, five hundred thirty-four thousand, two hundred fifty-seven".