123520215 has 64 divisors (see below), whose sum is σ = 257596416. Its totient is φ = 49047552.

The previous prime is 123520211. The next prime is 123520231. The reversal of 123520215 is 512025321.

It is not a de Polignac number, because 123520215 - 2² = 123520211 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 123520191 and 123520200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123520211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 20544 + ... + 25866.

It is an arithmetic number, because the mean of its divisors is an integer number (4024944).

Almost surely, 2^123520215 is an apocalyptic number.

123520215 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

123520215 is an abundant number, since it is smaller than the sum of its proper divisors (134076201).

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

123520215 is a wasteful number, since it uses less digits than its factorization.

123520215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5368.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 123520215 is about 11113.9648640798. The cubic root of 123520215 is about 498.0191158934.

Adding to 123520215 its reverse (512025321), we get a palindrome (635545536).

The spelling of 123520215 in words is "one hundred twenty-three million, five hundred twenty thousand, two hundred fifteen".