921189427 has 4 divisors (see below), whose sum is σ = 931539960. Its totient is φ = 910838896.

The previous prime is 921189413. The next prime is 921189431. The reversal of 921189427 is 724981129.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 921189427 - 2⁷ = 921189299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (921189457) 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, 5175133 + ... + 5175310.

It is an arithmetic number, because the mean of its divisors is an integer number (232884990).

Almost surely, 2^921189427 is an apocalyptic number.

921189427 is a deficient number, since it is larger than the sum of its proper divisors (10350533).

921189427 is a wasteful number, since it uses less digits than its factorization.

921189427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10350532.

The product of its digits is 72576, while the sum is 43.

The square root of 921189427 is about 30351.1025664637. The cubic root of 921189427 is about 973.0077846364.

The spelling of 921189427 in words is "nine hundred twenty-one million, one hundred eighty-nine thousand, four hundred twenty-seven".