123512420 has 24 divisors (see below), whose sum is σ = 262294200. Its totient is φ = 48849152.

The previous prime is 123512399. The next prime is 123512443. The reversal of 123512420 is 24215321.

It can be written as a sum of positive squares in 4 ways, for example, as 6310144 + 117202276 = 2512^2 + 10826^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 123512392 and 123512401.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32915 + ... + 36474.

It is an arithmetic number, because the mean of its divisors is an integer number (10928925).

Almost surely, 2^123512420 is an apocalyptic number.

123512420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

123512420 is an abundant number, since it is smaller than the sum of its proper divisors (138781780).

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

123512420 is a wasteful number, since it uses less digits than its factorization.

123512420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69487 (or 69485 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 123512420 is about 11113.6141736161. The cubic root of 123512420 is about 498.0086394957.

Adding to 123512420 its reverse (24215321), we get a palindrome (147727741).

The spelling of 123512420 in words is "one hundred twenty-three million, five hundred twelve thousand, four hundred twenty".