651221481 has 8 divisors (see below), whose sum is σ = 876261760. Its totient is φ = 430164432.

The previous prime is 651221479. The next prime is 651221489. The reversal of 651221481 is 184122156.

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

It is not a de Polignac number, because 651221481 - 2¹ = 651221479 is a prime.

It is a super-2 number, since 2×651221481² = 848178834631666722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (651221489) 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, 995425 + ... + 996078.

It is an arithmetic number, because the mean of its divisors is an integer number (109532720).

Almost surely, 2^651221481 is an apocalyptic number.

It is an amenable number.

651221481 is a deficient number, since it is larger than the sum of its proper divisors (225040279).

651221481 is a wasteful number, since it uses less digits than its factorization.

651221481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1991615.

The product of its digits is 3840, while the sum is 30.

The square root of 651221481 is about 25519.0415376440. The cubic root of 651221481 is about 866.7813784223.

The spelling of 651221481 in words is "six hundred fifty-one million, two hundred twenty-one thousand, four hundred eighty-one".