660577421 has 16 divisors (see below), whose sum is σ = 762289920. Its totient is φ = 560722560.

The previous prime is 660577417. The next prime is 660577441. The reversal of 660577421 is 124775066.

It is a cyclic number.

It is not a de Polignac number, because 660577421 - 2² = 660577417 is a prime.

It is a super-2 number, since 2×660577421² = 872725058270022482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660577441) 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, 786920 + ... + 787758.

It is an arithmetic number, because the mean of its divisors is an integer number (47643120).

Almost surely, 2^660577421 is an apocalyptic number.

It is an amenable number.

660577421 is a deficient number, since it is larger than the sum of its proper divisors (101712499).

660577421 is a wasteful number, since it uses less digits than its factorization.

660577421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1804.

The product of its (nonzero) digits is 70560, while the sum is 38.

The square root of 660577421 is about 25701.7007413906. The cubic root of 660577421 is about 870.9126025097.

The spelling of 660577421 in words is "six hundred sixty million, five hundred seventy-seven thousand, four hundred twenty-one".