856990551 has 8 divisors (see below), whose sum is σ = 1144520560. Its totient is φ = 570393792.

The previous prime is 856990493. The next prime is 856990597. The reversal of 856990551 is 155099658.

It is a happy number.

856990551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 856990551 - 2¹⁹ = 856466263 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 856990551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856940551) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 231166 + ... + 234843.

It is an arithmetic number, because the mean of its divisors is an integer number (143065070).

Almost surely, 2^856990551 is an apocalyptic number.

856990551 is a deficient number, since it is larger than the sum of its proper divisors (287530009).

856990551 is a wasteful number, since it uses less digits than its factorization.

856990551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 466625.

The product of its (nonzero) digits is 486000, while the sum is 48.

The square root of 856990551 is about 29274.4009503184. The cubic root of 856990551 is about 949.8579846807.

The spelling of 856990551 in words is "eight hundred fifty-six million, nine hundred ninety thousand, five hundred fifty-one".