861649488 has 400 divisors, whose sum is σ = 3119871744. Its totient is φ = 223948800.

The previous prime is 861649457. The next prime is 861649489. The reversal of 861649488 is 884946168.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861649489) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5706213 + ... + 5706363.

Almost surely, 2^861649488 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 861649488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1559935872).

861649488 is an abundant number, since it is smaller than the sum of its proper divisors (2258222256).

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

861649488 is a wasteful number, since it uses less digits than its factorization.

861649488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232 (or 217 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 54.

The square root of 861649488 is about 29353.8666618216. The cubic root of 861649488 is about 951.5761418462.

The spelling of 861649488 in words is "eight hundred sixty-one million, six hundred forty-nine thousand, four hundred eighty-eight".