721074420 has 192 divisors, whose sum is σ = 2462503680. Its totient is φ = 173721600.

The previous prime is 721074401. The next prime is 721074427. The reversal of 721074420 is 24470127.

It is a happy number.

721074420 is a `hidden beast` number, since 7 + 210 + 7 + 442 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721074427) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1383760 + ... + 1384280.

It is an arithmetic number, because the mean of its divisors is an integer number (12825540).

Almost surely, 2^721074420 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 721074420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1231251840).

721074420 is an abundant number, since it is smaller than the sum of its proper divisors (1741429260).

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

721074420 is a wasteful number, since it uses less digits than its factorization.

721074420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783 (or 775 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 27.

The square root of 721074420 is about 26852.8289012536. The cubic root of 721074420 is about 896.7265528165.

The spelling of 721074420 in words is "seven hundred twenty-one million, seventy-four thousand, four hundred twenty".