661953100898 has 8 divisors (see below), whose sum is σ = 1002760638300. Its totient is φ = 327699554800.

The previous prime is 661953100871. The next prime is 661953100931. The reversal of 661953100898 is 898001359166.

It can be written as a sum of positive squares in 2 ways, for example, as 512016095809 + 149937005089 = 715553^2 + 387217^2 .

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

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, 1638497573 + ... + 1638497976.

Almost surely, 2^661953100898 is an apocalyptic number.

661953100898 is a deficient number, since it is larger than the sum of its proper divisors (340807537402).

661953100898 is a wasteful number, since it uses less digits than its factorization.

661953100898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3276995652.

The product of its (nonzero) digits is 2799360, while the sum is 56.

The spelling of 661953100898 in words is "six hundred sixty-one billion, nine hundred fifty-three million, one hundred thousand, eight hundred ninety-eight".