661813726274 has 8 divisors (see below), whose sum is σ = 1035882354240. Its totient is φ = 316519608196.

The previous prime is 661813726261. The next prime is 661813726291. The reversal of 661813726274 is 472627318166.

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, 7193627414 + ... + 7193627505.

It is an arithmetic number, because the mean of its divisors is an integer number (129485294280).

Almost surely, 2^661813726274 is an apocalyptic number.

661813726274 is a deficient number, since it is larger than the sum of its proper divisors (374068627966).

661813726274 is a wasteful number, since it uses less digits than its factorization.

661813726274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14387254944.

The product of its digits is 4064256, while the sum is 53.

The spelling of 661813726274 in words is "six hundred sixty-one billion, eight hundred thirteen million, seven hundred twenty-six thousand, two hundred seventy-four".