721085418 has 24 divisors (see below), whose sum is σ = 1566263556. Its totient is φ = 239760000.

The previous prime is 721085401. The next prime is 721085471. The reversal of 721085418 is 814580127.

721085418 is a `hidden beast` number, since 7 + 2 + 108 + 541 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 454840929 + 266244489 = 21327^2 + 16317^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42733 + ... + 57168.

Almost surely, 2^721085418 is an apocalyptic number.

721085418 is an abundant number, since it is smaller than the sum of its proper divisors (845178138).

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

721085418 is a wasteful number, since it uses less digits than its factorization.

721085418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100310 (or 100307 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 36.

The square root of 721085418 is about 26853.0336833662. The cubic root of 721085418 is about 896.7311118228.

The spelling of 721085418 in words is "seven hundred twenty-one million, eighty-five thousand, four hundred eighteen".