890289721 has 4 divisors (see below), whose sum is σ = 893836944. Its totient is φ = 886742500.

The previous prime is 890289709. The next prime is 890289731. The reversal of 890289721 is 127982098.

890289721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 890289721 - 2²⁷ = 756071993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (890289731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1773235 + ... + 1773736.

It is an arithmetic number, because the mean of its divisors is an integer number (223459236).

Almost surely, 2^890289721 is an apocalyptic number.

It is an amenable number.

890289721 is a deficient number, since it is larger than the sum of its proper divisors (3547223).

890289721 is a wasteful number, since it uses less digits than its factorization.

890289721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3547222.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 890289721 is about 29837.7231202382. The cubic root of 890289721 is about 962.0045358194.

The spelling of 890289721 in words is "eight hundred ninety million, two hundred eighty-nine thousand, seven hundred twenty-one".