15601961 has 2 divisors, whose sum is σ = 15601962. Its totient is φ = 15601960.

The previous prime is 15601931. The next prime is 15601997. The reversal of 15601961 is 16910651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12816400 + 2785561 = 3580^2 + 1669^2 .

It is an emirp because it is prime and its reverse (16910651) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15601961 is a prime.

It is not a weakly prime, because it can be changed into another prime (15601921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7800980 + 7800981.

It is an arithmetic number, because the mean of its divisors is an integer number (7800981).

Almost surely, 2^15601961 is an apocalyptic number.

It is an amenable number.

15601961 is a deficient number, since it is larger than the sum of its proper divisors (1).

15601961 is an equidigital number, since it uses as much as digits as its factorization.

15601961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 15601961 is about 3949.9317715626. The cubic root of 15601961 is about 249.8770648911.

It can be divided in two parts, 156019 and 61, that multiplied together give a palindrome (9517159).

The spelling of 15601961 in words is "fifteen million, six hundred one thousand, nine hundred sixty-one".