616297681 has 4 divisors (see below), whose sum is σ = 616380772. Its totient is φ = 616214592.

The previous prime is 616297603. The next prime is 616297729. The reversal of 616297681 is 186792616.

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

It can be written as a sum of positive squares in 2 ways, for example, as 80838081 + 535459600 = 8991^2 + 23140^2 .

It is a cyclic number.

It is not a de Polignac number, because 616297681 - 2⁹ = 616297169 is a prime.

It is a super-2 number, since 2×616297681² = 759645663211955522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (616297601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29196 + ... + 45661.

It is an arithmetic number, because the mean of its divisors is an integer number (154095193).

Almost surely, 2^616297681 is an apocalyptic number.

It is an amenable number.

616297681 is a deficient number, since it is larger than the sum of its proper divisors (83091).

616297681 is an equidigital number, since it uses as much as digits as its factorization.

616297681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83090.

The product of its digits is 217728, while the sum is 46.

The square root of 616297681 is about 24825.3435222959. The cubic root of 616297681 is about 851.0012105278.

The spelling of 616297681 in words is "six hundred sixteen million, two hundred ninety-seven thousand, six hundred eighty-one".