858905640 has 192 divisors, whose sum is σ = 3023006400. Its totient is φ = 216888192.

The previous prime is 858905587. The next prime is 858905647. The reversal of 858905640 is 46509858.

858905640 is a `hidden beast` number, since 8 + 5 + 89 + 0 + 564 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (858905647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 388779 + ... + 390981.

It is an arithmetic number, because the mean of its divisors is an integer number (15744825).

Almost surely, 2^858905640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 858905640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1511503200).

858905640 is an abundant number, since it is smaller than the sum of its proper divisors (2164100760).

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

858905640 is a wasteful number, since it uses less digits than its factorization.

858905640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2261 (or 2232 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 858905640 is about 29307.0919744693. The cubic root of 858905640 is about 950.5649972437.

The spelling of 858905640 in words is "eight hundred fifty-eight million, nine hundred five thousand, six hundred forty".