1516681 has 2 divisors, whose sum is σ = 1516682. Its totient is φ = 1516680.

The previous prime is 1516663. The next prime is 1516687. The reversal of 1516681 is 1866151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1478656 + 38025 = 1216^2 + 195^2 .

It is a cyclic number.

It is not a de Polignac number, because 1516681 - 2¹¹ = 1514633 is a prime.

It is a super-2 number, since 2×1516681² = 4600642511522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1516687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 758340 + 758341.

It is an arithmetic number, because the mean of its divisors is an integer number (758341).

2^1516681 is an apocalyptic number.

It is an amenable number.

1516681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1516681 is an equidigital number, since it uses as much as digits as its factorization.

1516681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 28.

The square root of 1516681 is about 1231.5360327656. The cubic root of 1516681 is about 114.8941937978.

It can be divided in two parts, 1516 and 681, that added together give a cube (2197 = 13³).

The spelling of 1516681 in words is "one million, five hundred sixteen thousand, six hundred eighty-one".