901019721 has 16 divisors (see below), whose sum is σ = 1404913664. Its totient is φ = 502894224.

The previous prime is 901019701. The next prime is 901019789. The reversal of 901019721 is 127910109.

901019721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 901019721 - 2¹⁰ = 901018697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (901019701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 498001 + ... + 499806.

It is an arithmetic number, because the mean of its divisors is an integer number (87807104).

Almost surely, 2^901019721 is an apocalyptic number.

It is an amenable number.

901019721 is a deficient number, since it is larger than the sum of its proper divisors (503893943).

901019721 is a wasteful number, since it uses less digits than its factorization.

901019721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 997860.

The product of its (nonzero) digits is 1134, while the sum is 30.

The square root of 901019721 is about 30016.9905386932. The cubic root of 901019721 is about 965.8538876437.

The spelling of 901019721 in words is "nine hundred one million, nineteen thousand, seven hundred twenty-one".