1451618921 has 4 divisors (see below), whose sum is σ = 1451717844. Its totient is φ = 1451520000.

The previous prime is 1451618893. The next prime is 1451618939. The reversal of 1451618921 is 1298161541.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 550418521 + 901200400 = 23461^2 + 30020^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1451618921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1451618621) 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, 22580 + ... + 58421.

It is an arithmetic number, because the mean of its divisors is an integer number (362929461).

Almost surely, 2^1451618921 is an apocalyptic number.

It is an amenable number.

1451618921 is a deficient number, since it is larger than the sum of its proper divisors (98923).

1451618921 is an equidigital number, since it uses as much as digits as its factorization.

1451618921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98922.

The product of its digits is 17280, while the sum is 38.

The square root of 1451618921 is about 38100.1170733109. The cubic root of 1451618921 is about 1132.2722755364.

The spelling of 1451618921 in words is "one billion, four hundred fifty-one million, six hundred eighteen thousand, nine hundred twenty-one".