1516501661 has 2 divisors, whose sum is σ = 1516501662. Its totient is φ = 1516501660.

The previous prime is 1516501627. The next prime is 1516501681. The reversal of 1516501661 is 1661056151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1129632100 + 386869561 = 33610^2 + 19669^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1516501661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1516501681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 758250830 + 758250831.

It is an arithmetic number, because the mean of its divisors is an integer number (758250831).

Almost surely, 2^1516501661 is an apocalyptic number.

It is an amenable number.

1516501661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1516501661 is an equidigital number, since it uses as much as digits as its factorization.

1516501661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5400, while the sum is 32.

The square root of 1516501661 is about 38942.2862836788. The cubic root of 1516501661 is about 1148.8966508846.

The spelling of 1516501661 in words is "one billion, five hundred sixteen million, five hundred one thousand, six hundred sixty-one".