102105990 has 192 divisors, whose sum is σ = 320785920. Its totient is φ = 22049280.

The previous prime is 102105989. The next prime is 102106007. The reversal of 102105990 is 99501201.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1523937 + ... + 1524003.

It is an arithmetic number, because the mean of its divisors is an integer number (1670760).

Almost surely, 2^102105990 is an apocalyptic number.

102105990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 102105990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (160392960).

102105990 is an abundant number, since it is smaller than the sum of its proper divisors (218679930).

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

102105990 is a wasteful number, since it uses less digits than its factorization.

102105990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 27.

The square root of 102105990 is about 10104.7508628367. The cubic root of 102105990 is about 467.3946534532.

The spelling of 102105990 in words is "one hundred two million, one hundred five thousand, nine hundred ninety".