721242144 has 240 divisors, whose sum is σ = 2451068928. Its totient is φ = 203793408.

The previous prime is 721242127. The next prime is 721242173. The reversal of 721242144 is 441242127.

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

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2304132 + ... + 2304444.

Almost surely, 2^721242144 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 721242144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1225534464).

721242144 is an abundant number, since it is smaller than the sum of its proper divisors (1729826784).

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

721242144 is a wasteful number, since it uses less digits than its factorization.

721242144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469 (or 452 counting only the distinct ones).

The product of its digits is 3584, while the sum is 27.

The square root of 721242144 is about 26855.9517425840. The cubic root of 721242144 is about 896.7960744915.

The spelling of 721242144 in words is "seven hundred twenty-one million, two hundred forty-two thousand, one hundred forty-four".