851005440 has 416 divisors, whose sum is σ = 3223977600. Its totient is φ = 214990848.

The previous prime is 851005433. The next prime is 851005489. The reversal of 851005440 is 44500158.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44789751 + ... + 44789769.

Almost surely, 2^851005440 is an apocalyptic number.

851005440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 851005440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1611988800).

851005440 is an abundant number, since it is smaller than the sum of its proper divisors (2372972160).

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

851005440 is an frugal number, since it uses more digits than its factorization.

851005440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 851005440 is about 29171.9975318798. The cubic root of 851005440 is about 947.6415885948.

Adding to 851005440 its reverse (44500158), we get a palindrome (895505598).

The spelling of 851005440 in words is "eight hundred fifty-one million, five thousand, four hundred forty".