12511820 has 12 divisors (see below), whose sum is σ = 26274864. Its totient is φ = 5004720.

The previous prime is 12511787. The next prime is 12511843. The reversal of 12511820 is 2811521.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 625591 = 12511820 / (1 + 2 + 5 + 1 + 1 + 8 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 12511792 and 12511801.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 312776 + ... + 312815.

It is an arithmetic number, because the mean of its divisors is an integer number (2189572).

Almost surely, 2^12511820 is an apocalyptic number.

12511820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12511820 is an abundant number, since it is smaller than the sum of its proper divisors (13763044).

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

12511820 is a wasteful number, since it uses less digits than its factorization.

12511820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 625600 (or 625598 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 12511820 is about 3537.2051113838. The cubic root of 12511820 is about 232.1525700754.

It can be divided in two parts, 12511 and 820, that added together give a palindrome (13331).

The spelling of 12511820 in words is "twelve million, five hundred eleven thousand, eight hundred twenty".