816255840 has 48 divisors (see below), whose sum is σ = 2571207408. Its totient is φ = 217668096.

The previous prime is 816255829. The next prime is 816255859. The reversal of 816255840 is 48552618.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 849787 + ... + 850746.

It is an arithmetic number, because the mean of its divisors is an integer number (53566821).

Almost surely, 2^816255840 is an apocalyptic number.

816255840 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

816255840 is an abundant number, since it is smaller than the sum of its proper divisors (1754951568).

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

816255840 is a wasteful number, since it uses less digits than its factorization.

816255840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1700551 (or 1700543 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 39.

The square root of 816255840 is about 28570.1914589315. The cubic root of 816255840 is about 934.5633962982.

The spelling of 816255840 in words is "eight hundred sixteen million, two hundred fifty-five thousand, eight hundred forty".