856149994669 has 4 divisors (see below), whose sum is σ = 856381327740. Its totient is φ = 855918661600.

The previous prime is 856149994621. The next prime is 856149994673. The reversal of 856149994669 is 966499941658.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 199061422569 + 657088572100 = 446163^2 + 810610^2 .

It is a cyclic number.

It is not a de Polignac number, because 856149994669 - 2¹³ = 856149986477 is a prime.

It is a super-2 number, since 2×856149994669² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 856149994595 and 856149994604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856149994769) 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 in 3 ways as a sum of consecutive naturals, for example, 115660984 + ... + 115668385.

It is an arithmetic number, because the mean of its divisors is an integer number (214095331935).

Almost surely, 2^856149994669 is an apocalyptic number.

It is an amenable number.

856149994669 is a deficient number, since it is larger than the sum of its proper divisors (231333071).

856149994669 is a wasteful number, since it uses less digits than its factorization.

856149994669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231333070.

The product of its digits is 906992640, while the sum is 76.

The spelling of 856149994669 in words is "eight hundred fifty-six billion, one hundred forty-nine million, nine hundred ninety-four thousand, six hundred sixty-nine".