66906897 has 16 divisors (see below), whose sum is σ = 94052352. Its totient is φ = 42244560.

The previous prime is 66906887. The next prime is 66906901. The reversal of 66906897 is 79860966.

It is a happy number.

It is not a de Polignac number, because 66906897 - 2⁸ = 66906641 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66906887) 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, 3283 + ... + 12024.

It is an arithmetic number, because the mean of its divisors is an integer number (5878272).

Almost surely, 2^66906897 is an apocalyptic number.

It is an amenable number.

66906897 is a deficient number, since it is larger than the sum of its proper divisors (27145455).

66906897 is a wasteful number, since it uses less digits than its factorization.

66906897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15388.

The product of its (nonzero) digits is 979776, while the sum is 51.

The square root of 66906897 is about 8179.6636238907. The cubic root of 66906897 is about 405.9665923315.

The spelling of 66906897 in words is "sixty-six million, nine hundred six thousand, eight hundred ninety-seven".