661057200 has 210 divisors, whose sum is σ = 2382245964. Its totient is φ = 176204160.

The previous prime is 661057169. The next prime is 661057211. The reversal of 661057200 is 2750166.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

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 41 ways as a sum of consecutive naturals, for example, 290467 + ... + 292733.

Almost surely, 2^661057200 is an apocalyptic number.

661057200 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661057200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1191122982).

661057200 is an abundant number, since it is smaller than the sum of its proper divisors (1721188764).

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

661057200 is a wasteful number, since it uses less digits than its factorization.

661057200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2303 (or 2277 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 661057200 is about 25711.0326513736. The cubic root of 661057200 is about 871.1234001363.

The spelling of 661057200 in words is "six hundred sixty-one million, fifty-seven thousand, two hundred".