102138408 has 80 divisors (see below), whose sum is σ = 288134880. Its totient is φ = 33802272.

The previous prime is 102138401. The next prime is 102138437. The reversal of 102138408 is 804831201.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (102138401) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 105141 + ... + 106107.

It is an arithmetic number, because the mean of its divisors is an integer number (3601686).

Almost surely, 2^102138408 is an apocalyptic number.

102138408 is a gapful number since it is divisible by the number (18) 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 102138408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144067440).

102138408 is an abundant number, since it is smaller than the sum of its proper divisors (185996472).

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

102138408 is a wasteful number, since it uses less digits than its factorization.

102138408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1148 (or 1135 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 102138408 is about 10106.3548324804. The cubic root of 102138408 is about 467.4441131588. Note that the first 3 decimals are identical.

Adding to 102138408 its reverse (804831201), we get a palindrome (906969609).

The spelling of 102138408 in words is "one hundred two million, one hundred thirty-eight thousand, four hundred eight".