856019440 has 40 divisors (see below), whose sum is σ = 2009969568. Its totient is φ = 339014400.

The previous prime is 856019387. The next prime is 856019441. The reversal of 856019440 is 44910658.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 856019440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856019441) 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, 44892 + ... + 61051.

Almost surely, 2^856019440 is an apocalyptic number.

856019440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

856019440 is an abundant number, since it is smaller than the sum of its proper divisors (1153950128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

856019440 is a wasteful number, since it uses less digits than its factorization.

856019440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106057 (or 106051 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The square root of 856019440 is about 29257.8098975299. The cubic root of 856019440 is about 949.4990673925.

The spelling of 856019440 in words is "eight hundred fifty-six million, nineteen thousand, four hundred forty".