661248004 has 24 divisors (see below), whose sum is σ = 1163554560. Its totient is φ = 328810464.

The previous prime is 661247941. The next prime is 661248037. The reversal of 661248004 is 400842166.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1078402 + ... + 1079014.

It is an arithmetic number, because the mean of its divisors is an integer number (48481440).

Almost surely, 2^661248004 is an apocalyptic number.

It is an amenable number.

661248004 is a deficient number, since it is larger than the sum of its proper divisors (502306556).

661248004 is a wasteful number, since it uses less digits than its factorization.

661248004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1659 (or 1657 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 31.

The square root of 661248004 is about 25714.7429308558. The cubic root of 661248004 is about 871.2072042005.

The spelling of 661248004 in words is "six hundred sixty-one million, two hundred forty-eight thousand, four".