863686428 has 96 divisors (see below), whose sum is σ = 2335350528. Its totient is φ = 245529600.

The previous prime is 863686403. The next prime is 863686469. The reversal of 863686428 is 824686368.

It is a happy number.

It is a super-2 number, since 2×863686428² = 1491908491822798368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

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, 1249563 + ... + 1250253.

It is an arithmetic number, because the mean of its divisors is an integer number (24326568).

Almost surely, 2^863686428 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 863686428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1167675264).

863686428 is an abundant number, since it is smaller than the sum of its proper divisors (1471664100).

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

863686428 is a wasteful number, since it uses less digits than its factorization.

863686428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1283 (or 1281 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 51.

The square root of 863686428 is about 29388.5424613062. The cubic root of 863686428 is about 952.3253939696.

The spelling of 863686428 in words is "eight hundred sixty-three million, six hundred eighty-six thousand, four hundred twenty-eight".