661421124 has 144 divisors (see below), whose sum is σ = 2079168000. Its totient is φ = 172627200.

The previous prime is 661421077. The next prime is 661421219. The reversal of 661421124 is 421124166.

661421124 is a `hidden beast` number, since 6 + 614 + 21 + 1 + 24 = 666.

661421124 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 329877 + ... + 331875.

Almost surely, 2^661421124 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 661421124, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1039584000).

661421124 is an abundant number, since it is smaller than the sum of its proper divisors (1417746876).

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

661421124 is a wasteful number, since it uses less digits than its factorization.

661421124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2130 (or 2125 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 661421124 is about 25718.1088729323. The cubic root of 661421124 is about 871.2832272307.

The spelling of 661421124 in words is "six hundred sixty-one million, four hundred twenty-one thousand, one hundred twenty-four".