3917160721 has 2 divisors, whose sum is σ = 3917160722. Its totient is φ = 3917160720.

The previous prime is 3917160719. The next prime is 3917160749. The reversal of 3917160721 is 1270617193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3727713025 + 189447696 = 61055^2 + 13764^2 .

It is an emirp because it is prime and its reverse (1270617193) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3917160721 - 2¹ = 3917160719 is a prime.

It is a super-2 number, since 2×3917160721² = 30688296228290479682, which contains 22 as substring.

Together with 3917160719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (3917160701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1958580360 + 1958580361.

It is an arithmetic number, because the mean of its divisors is an integer number (1958580361).

Almost surely, 2^3917160721 is an apocalyptic number.

It is an amenable number.

3917160721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3917160721 is an equidigital number, since it uses as much as digits as its factorization.

3917160721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 3917160721 is about 62587.2249025310. The cubic root of 3917160721 is about 1576.3662582982.

The spelling of 3917160721 in words is "three billion, nine hundred seventeen million, one hundred sixty thousand, seven hundred twenty-one".