671643400 has 24 divisors (see below), whose sum is σ = 1561571370. Its totient is φ = 268657280.

The previous prime is 671643383. The next prime is 671643431. The reversal of 671643400 is 4346176.

It can be written as a sum of positive squares in 3 ways, for example, as 582643044 + 89000356 = 24138^2 + 9434^2 .

It is a super-2 number, since 2×671643400² = 902209713527120000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1678909 + ... + 1679308.

Almost surely, 2^671643400 is an apocalyptic number.

It is an amenable number.

671643400 is an abundant number, since it is smaller than the sum of its proper divisors (889927970).

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

671643400 is a wasteful number, since it uses less digits than its factorization.

671643400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3358233 (or 3358224 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 671643400 is about 25916.0838090943. The cubic root of 671643400 is about 875.7488663849.

Adding to 671643400 its reverse (4346176), we get a palindrome (675989576).

The spelling of 671643400 in words is "six hundred seventy-one million, six hundred forty-three thousand, four hundred".