661372050 has 48 divisors (see below), whose sum is σ = 1654760160. Its totient is φ = 174800640.

The previous prime is 661372039. The next prime is 661372051. The reversal of 661372050 is 50273166.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 661371999 and 661372017.

It is not an unprimeable number, because it can be changed into a prime (661372051) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 2560 + ... + 36459.

It is an arithmetic number, because the mean of its divisors is an integer number (34474170).

Almost surely, 2^661372050 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661372050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (827380080).

661372050 is an abundant number, since it is smaller than the sum of its proper divisors (993388110).

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

661372050 is a wasteful number, since it uses less digits than its factorization.

661372050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39147 (or 39142 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 30.

The square root of 661372050 is about 25717.1547804185. The cubic root of 661372050 is about 871.2616784730.

The spelling of 661372050 in words is "six hundred sixty-one million, three hundred seventy-two thousand, fifty".