855615689 has 2 divisors, whose sum is σ = 855615690. Its totient is φ = 855615688.

The previous prime is 855615671. The next prime is 855615697. The reversal of 855615689 is 986516558.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 825585289 + 30030400 = 28733^2 + 5480^2 .

It is a cyclic number.

It is not a de Polignac number, because 855615689 - 2²⁸ = 587180233 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 855615689.

It is not a weakly prime, because it can be changed into another prime (855615289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 427807844 + 427807845.

It is an arithmetic number, because the mean of its divisors is an integer number (427807845).

Almost surely, 2^855615689 is an apocalyptic number.

It is an amenable number.

855615689 is a deficient number, since it is larger than the sum of its proper divisors (1).

855615689 is an equidigital number, since it uses as much as digits as its factorization.

855615689 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2592000, while the sum is 53.

The square root of 855615689 is about 29250.9091995446. The cubic root of 855615689 is about 949.3497633511.

The spelling of 855615689 in words is "eight hundred fifty-five million, six hundred fifteen thousand, six hundred eighty-nine".