15681228406889 has 2 divisors, whose sum is σ = 15681228406890. Its totient is φ = 15681228406888.

The previous prime is 15681228406829. The next prime is 15681228406931. The reversal of 15681228406889 is 98860482218651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14246963485225 + 1434264921664 = 3774515^2 + 1197608^2 .

It is a cyclic number.

It is not a de Polignac number, because 15681228406889 - 2⁸ = 15681228406633 is a prime.

It is not a weakly prime, because it can be changed into another prime (15681228406819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7840614203444 + 7840614203445.

It is an arithmetic number, because the mean of its divisors is an integer number (7840614203445).

Almost surely, 2^{15681228406889} is an apocalyptic number.

It is an amenable number.

15681228406889 is a deficient number, since it is larger than the sum of its proper divisors (1).

15681228406889 is an equidigital number, since it uses as much as digits as its factorization.

15681228406889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 106168320, while the sum is 68.

The spelling of 15681228406889 in words is "fifteen trillion, six hundred eighty-one billion, two hundred twenty-eight million, four hundred six thousand, eight hundred eighty-nine".