1212112820 has 24 divisors (see below), whose sum is σ = 2559664800. Its totient is φ = 482135072.

The previous prime is 1212112789. The next prime is 1212112849. The reversal of 1212112820 is 282112121.

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 = 1212112792 and 1212112801.

It is a congruent number.

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, 165710 + ... + 172869.

It is an arithmetic number, because the mean of its divisors is an integer number (106652700).

Almost surely, 2^1212112820 is an apocalyptic number.

1212112820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1212112820 is an abundant number, since it is smaller than the sum of its proper divisors (1347551980).

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

1212112820 is a wasteful number, since it uses less digits than its factorization.

1212112820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338767 (or 338765 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 1212112820 is about 34815.4106682659. The cubic root of 1212112820 is about 1066.2221035872. Note that the first 3 decimals are identical.

Adding to 1212112820 its reverse (282112121), we get a palindrome (1494224941).

The spelling of 1212112820 in words is "one billion, two hundred twelve million, one hundred twelve thousand, eight hundred twenty".