102138405 has 16 divisors (see below), whose sum is σ = 165010560. Its totient is φ = 53944128.

The previous prime is 102138401. The next prime is 102138437. The reversal of 102138405 is 504831201.

It is not a de Polignac number, because 102138405 - 2² = 102138401 is a prime.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 31510 + ... + 34599.

It is an arithmetic number, because the mean of its divisors is an integer number (10313160).

Almost surely, 2^102138405 is an apocalyptic number.

102138405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

102138405 is a deficient number, since it is larger than the sum of its proper divisors (62872155).

102138405 is a wasteful number, since it uses less digits than its factorization.

102138405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66220.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 102138405 is about 10106.3546840589. The cubic root of 102138405 is about 467.4441085822. Note that the first 3 decimals are identical.

Adding to 102138405 its reverse (504831201), we get a palindrome (606969606).

The spelling of 102138405 in words is "one hundred two million, one hundred thirty-eight thousand, four hundred five".