667728570 has 32 divisors (see below), whose sum is σ = 1628824320. Its totient is φ = 175141440.

The previous prime is 667728569. The next prime is 667728599. The reversal of 667728570 is 75827766.

It is a super-2 number, since 2×667728570² = 891722886388489800, which contains 22 as substring.

It is a Curzon number.

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, 180610 + ... + 184269.

It is an arithmetic number, because the mean of its divisors is an integer number (50900760).

Almost surely, 2^667728570 is an apocalyptic number.

667728570 is an abundant number, since it is smaller than the sum of its proper divisors (961095750).

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

667728570 is a wasteful number, since it uses less digits than its factorization.

667728570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364950.

The product of its (nonzero) digits is 987840, while the sum is 48.

The square root of 667728570 is about 25840.4444621218. Note that the first 4 decimals coincide. The cubic root of 667728570 is about 874.0440476869.

The spelling of 667728570 in words is "six hundred sixty-seven million, seven hundred twenty-eight thousand, five hundred seventy".