12151820 has 24 divisors (see below), whose sum is σ = 26629344. Its totient is φ = 4649216.

The previous prime is 12151801. The next prime is 12151823. The reversal of 12151820 is 2815121.

It is a happy number.

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 = 12151792 and 12151801.

It is not an unprimeable number, because it can be changed into a prime (12151823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12749 + ... + 13668.

It is an arithmetic number, because the mean of its divisors is an integer number (1109556).

Almost surely, 2^12151820 is an apocalyptic number.

12151820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12151820 is an abundant number, since it is smaller than the sum of its proper divisors (14477524).

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

12151820 is a wasteful number, since it uses less digits than its factorization.

12151820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26449 (or 26447 counting only the distinct ones).

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

The square root of 12151820 is about 3485.9460695771. The cubic root of 12151820 is about 229.9043080188.

Adding to 12151820 its reverse (2815121), we get a palindrome (14966941).

The spelling of 12151820 in words is "twelve million, one hundred fifty-one thousand, eight hundred twenty".