99861390 has 64 divisors (see below), whose sum is σ = 267174720. Its totient is φ = 26542080.

The previous prime is 99861389. The next prime is 99861401. The reversal of 99861390 is 9316899.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 155470 + ... + 156110.

It is an arithmetic number, because the mean of its divisors is an integer number (4174605).

Almost surely, 2^99861390 is an apocalyptic number.

99861390 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 99861390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133587360).

99861390 is an abundant number, since it is smaller than the sum of its proper divisors (167313330).

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

99861390 is a wasteful number, since it uses less digits than its factorization.

99861390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1234 (or 1228 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 99861390 is about 9993.0670967426. The cubic root of 99861390 is about 463.9443273226.

The spelling of 99861390 in words is "ninety-nine million, eight hundred sixty-one thousand, three hundred ninety".