863649840 has 160 divisors (see below), whose sum is σ = 2793035520. Its totient is φ = 220566528.

The previous prime is 863649833. The next prime is 863649869. The reversal of 863649840 is 48946368.

It is a super-2 number, since 2×863649840² = 1491782092264051200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 863649840.

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, 546171 + ... + 547749.

It is an arithmetic number, because the mean of its divisors is an integer number (17456472).

Almost surely, 2^863649840 is an apocalyptic number.

863649840 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 863649840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1396517760).

863649840 is an abundant number, since it is smaller than the sum of its proper divisors (1929385680).

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

863649840 is a wasteful number, since it uses less digits than its factorization.

863649840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691 (or 1685 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 48.

The square root of 863649840 is about 29387.9199672246. The cubic root of 863649840 is about 952.3119461208.

The spelling of 863649840 in words is "eight hundred sixty-three million, six hundred forty-nine thousand, eight hundred forty".