840402864 has 320 divisors, whose sum is σ = 2889338880. Its totient is φ = 231787008.

The previous prime is 840402863. The next prime is 840402883. The reversal of 840402864 is 468204048.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (840402863) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11512332 + ... + 11512404.

It is an arithmetic number, because the mean of its divisors is an integer number (9029184).

Almost surely, 2^840402864 is an apocalyptic number.

840402864 is a gapful number since it is divisible by the number (84) 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 840402864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1444669440).

840402864 is an abundant number, since it is smaller than the sum of its proper divisors (2048936016).

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

840402864 is an equidigital number, since it uses as much as digits as its factorization.

840402864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 36.

The square root of 840402864 is about 28989.7027235534. The cubic root of 840402864 is about 943.6896123576.

The spelling of 840402864 in words is "eight hundred forty million, four hundred two thousand, eight hundred sixty-four".