661666146 has 128 divisors (see below), whose sum is σ = 1558828800. Its totient is φ = 185794560.

The previous prime is 661666133. The next prime is 661666219. The reversal of 661666146 is 641666166.

Its product of digits (186624) is a multiple of the sum of its prime divisors (324).

It is a junction number, because it is equal to n+sod(n) for n = 661666098 and 661666107.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3428226 + ... + 3428418.

It is an arithmetic number, because the mean of its divisors is an integer number (12178350).

Almost surely, 2^661666146 is an apocalyptic number.

661666146 is an abundant number, since it is smaller than the sum of its proper divisors (897162654).

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

661666146 is a wasteful number, since it uses less digits than its factorization.

661666146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324.

The product of its digits is 186624, while the sum is 42.

The square root of 661666146 is about 25722.8720402680. The cubic root of 661666146 is about 871.3908022662.

The spelling of 661666146 in words is "six hundred sixty-one million, six hundred sixty-six thousand, one hundred forty-six".