8451427721 has 8 divisors (see below), whose sum is σ = 9220406688. Its totient is φ = 7682560000.

The previous prime is 8451427709. The next prime is 8451427723. The reversal of 8451427721 is 1277241548.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8451427721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8451427723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266606 + ... + 296616.

It is an arithmetic number, because the mean of its divisors is an integer number (1152550836).

Almost surely, 2^8451427721 is an apocalyptic number.

It is an amenable number.

8451427721 is a deficient number, since it is larger than the sum of its proper divisors (768978967).

8451427721 is a wasteful number, since it uses less digits than its factorization.

8451427721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55623.

The product of its digits is 125440, while the sum is 41.

The square root of 8451427721 is about 91931.6470047176. The cubic root of 8451427721 is about 2036.9327641042.

The spelling of 8451427721 in words is "eight billion, four hundred fifty-one million, four hundred twenty-seven thousand, seven hundred twenty-one".