66666522 has 32 divisors (see below), whose sum is σ = 143902080. Its totient is φ = 20468160.

The previous prime is 66666517. The next prime is 66666557. The reversal of 66666522 is 22566666.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a nialpdrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64147 + ... + 65177.

It is an arithmetic number, because the mean of its divisors is an integer number (4496940).

Almost surely, 2^66666522 is an apocalyptic number.

66666522 is an abundant number, since it is smaller than the sum of its proper divisors (77235558).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66666522 is a wasteful number, since it uses less digits than its factorization.

66666522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1878.

The product of its digits is 155520, while the sum is 39.

The square root of 66666522 is about 8164.9569502846. The cubic root of 66666522 is about 405.4798397407.

The spelling of 66666522 in words is "sixty-six million, six hundred sixty-six thousand, five hundred twenty-two".