661849797 has 32 divisors (see below), whose sum is σ = 1070496000. Its totient is φ = 355074048.

The previous prime is 661849759. The next prime is 661849813. The reversal of 661849797 is 797948166.

661849797 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 661849797 - 2²³ = 653461189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661849897) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 158229 + ... + 162357.

It is an arithmetic number, because the mean of its divisors is an integer number (33453000).

Almost surely, 2^661849797 is an apocalyptic number.

It is an amenable number.

661849797 is a deficient number, since it is larger than the sum of its proper divisors (408646203).

661849797 is a wasteful number, since it uses less digits than its factorization.

661849797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4605.

The product of its digits is 4572288, while the sum is 57.

The square root of 661849797 is about 25726.4415922607. The cubic root of 661849797 is about 871.4714154221.

The spelling of 661849797 in words is "six hundred sixty-one million, eight hundred forty-nine thousand, seven hundred ninety-seven".