669440890 has 8 divisors (see below), whose sum is σ = 1204993620. Its totient is φ = 267776352.

The previous prime is 669440867. The next prime is 669440903. The reversal of 669440890 is 98044966.

It can be written as a sum of positive squares in 2 ways, for example, as 668894769 + 546121 = 25863^2 + 739^2 .

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

It is a super-2 number, since 2×669440890² = 896302210407984200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 669440890.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33472035 + ... + 33472054.

Almost surely, 2^669440890 is an apocalyptic number.

669440890 is a deficient number, since it is larger than the sum of its proper divisors (535552730).

669440890 is a wasteful number, since it uses less digits than its factorization.

669440890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66944096.

The product of its (nonzero) digits is 373248, while the sum is 46.

The square root of 669440890 is about 25873.5558051073. Note that the first 3 decimals coincide. The cubic root of 669440890 is about 874.7905414282.

The spelling of 669440890 in words is "six hundred sixty-nine million, four hundred forty thousand, eight hundred ninety".