661479969 has 8 divisors (see below), whose sum is σ = 905810560. Its totient is φ = 429068016.

The previous prime is 661479943. The next prime is 661479991. The reversal of 661479969 is 969974166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 661479969 - 2¹² = 661475873 is a prime.

It is a super-2 number, since 2×661479969² = 875111498776481922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (661479919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2979529 + ... + 2979750.

It is an arithmetic number, because the mean of its divisors is an integer number (113226320).

Almost surely, 2^661479969 is an apocalyptic number.

It is an amenable number.

661479969 is a deficient number, since it is larger than the sum of its proper divisors (244330591).

661479969 is a wasteful number, since it uses less digits than its factorization.

661479969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5959319.

The product of its digits is 4408992, while the sum is 57.

The square root of 661479969 is about 25719.2528857275. The cubic root of 661479969 is about 871.3090651017.

The spelling of 661479969 in words is "six hundred sixty-one million, four hundred seventy-nine thousand, nine hundred sixty-nine".