102123540 has 72 divisors (see below), whose sum is σ = 313021800. Its totient is φ = 26947584.

The previous prime is 102123523. The next prime is 102123547. The reversal of 102123540 is 45321201.

102123540 is a `hidden beast` number, since 1 + 0 + 2 + 123 + 540 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 4588164 + 97535376 = 2142^2 + 9876^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102123547) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14536 + ... + 20384.

It is an arithmetic number, because the mean of its divisors is an integer number (4347525).

Almost surely, 2^102123540 is an apocalyptic number.

102123540 is a gapful number since it is divisible by the number (10) 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 102123540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156510900).

102123540 is an abundant number, since it is smaller than the sum of its proper divisors (210898260).

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

102123540 is a wasteful number, since it uses less digits than its factorization.

102123540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5961 (or 5956 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 102123540 is about 10105.6192289241. The cubic root of 102123540 is about 467.4214305511.

Adding to 102123540 its reverse (45321201), we get a palindrome (147444741).

The spelling of 102123540 in words is "one hundred two million, one hundred twenty-three thousand, five hundred forty".