661368243200 has 132 divisors (see below), whose sum is σ = 1873591784832. Its totient is φ = 226754764800.

The previous prime is 661368243197. The next prime is 661368243223. The reversal of 661368243200 is 2342863166.

It is a super-2 number, since 2×661368243200² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1666136 + ... + 2024535.

Almost surely, 2^661368243200 is an apocalyptic number.

It is an amenable number.

661368243200 is an abundant number, since it is smaller than the sum of its proper divisors (1212223541632).

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

661368243200 is a wasteful number, since it uses less digits than its factorization.

661368243200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3690708 (or 3690685 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 41.

The spelling of 661368243200 in words is "six hundred sixty-one billion, three hundred sixty-eight million, two hundred forty-three thousand, two hundred".