66906854 has 12 divisors (see below), whose sum is σ = 116745804. Its totient is φ = 28674324.

The previous prime is 66906821. The next prime is 66906859. The reversal of 66906854 is 45860966.

It is a super-2 number, since 2×66906854² = 8953054224354632, which contains 22 as substring.

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66906859) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 341264 + ... + 341459.

It is an arithmetic number, because the mean of its divisors is an integer number (9728817).

Almost surely, 2^66906854 is an apocalyptic number.

66906854 is a deficient number, since it is larger than the sum of its proper divisors (49838950).

66906854 is a wasteful number, since it uses less digits than its factorization.

66906854 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 682739 (or 682732 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 44.

The square root of 66906854 is about 8179.6609954203. The cubic root of 66906854 is about 405.9665053620.

The spelling of 66906854 in words is "sixty-six million, nine hundred six thousand, eight hundred fifty-four".