2516661709 has 2 divisors, whose sum is σ = 2516661710. Its totient is φ = 2516661708.

The previous prime is 2516661643. The next prime is 2516661733. The reversal of 2516661709 is 9071666152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2318133609 + 198528100 = 48147^2 + 14090^2 .

It is a cyclic number.

It is not a de Polignac number, because 2516661709 - 2¹¹ = 2516659661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2516661769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1258330854 + 1258330855.

It is an arithmetic number, because the mean of its divisors is an integer number (1258330855).

Almost surely, 2^2516661709 is an apocalyptic number.

It is an amenable number.

2516661709 is a deficient number, since it is larger than the sum of its proper divisors (1).

2516661709 is an equidigital number, since it uses as much as digits as its factorization.

2516661709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 2516661709 is about 50166.3403987175. The cubic root of 2516661709 is about 1360.2172571387.

It can be divided in two parts, 2516 and 661709, that added together give a square (664225 = 815²).

The spelling of 2516661709 in words is "two billion, five hundred sixteen million, six hundred sixty-one thousand, seven hundred nine".