661796352 has 240 divisors, whose sum is σ = 2281126320. Its totient is φ = 188891136.

The previous prime is 661796329. The next prime is 661796357. The reversal of 661796352 is 253697166.

661796352 is a `hidden beast` number, since 6 + 6 + 1 + 7 + 9 + 635 + 2 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 661796298 and 661796307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661796357) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 676888 + ... + 677864.

It is an arithmetic number, because the mean of its divisors is an integer number (9504693).

Almost surely, 2^661796352 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661796352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1140563160).

661796352 is an abundant number, since it is smaller than the sum of its proper divisors (1619329968).

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

661796352 is an equidigital number, since it uses as much as digits as its factorization.

661796352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018 (or 989 counting only the distinct ones).

The product of its digits is 408240, while the sum is 45.

The square root of 661796352 is about 25725.4028539885. The cubic root of 661796352 is about 871.4479574090.

The spelling of 661796352 in words is "six hundred sixty-one million, seven hundred ninety-six thousand, three hundred fifty-two".