989621421 has 4 divisors (see below), whose sum is σ = 1319495232. Its totient is φ = 659747612.

The previous prime is 989621417. The next prime is 989621429. The reversal of 989621421 is 124126989.

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 989621421 - 2² = 989621417 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989621429) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 164936901 + ... + 164936906.

It is an arithmetic number, because the mean of its divisors is an integer number (329873808).

Almost surely, 2^989621421 is an apocalyptic number.

It is an amenable number.

989621421 is a deficient number, since it is larger than the sum of its proper divisors (329873811).

989621421 is a wasteful number, since it uses less digits than its factorization.

989621421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329873810.

The product of its digits is 62208, while the sum is 42.

The square root of 989621421 is about 31458.2488546327. The cubic root of 989621421 is about 996.5284358552.

The spelling of 989621421 in words is "nine hundred eighty-nine million, six hundred twenty-one thousand, four hundred twenty-one".