1212863220 has 120 divisors (see below), whose sum is σ = 3927694848. Its totient is φ = 312984000.

The previous prime is 1212863207. The next prime is 1212863227. The reversal of 1212863220 is 223682121.

1212863220 is a `hidden beast` number, since 1 + 2 + 1 + 2 + 8 + 632 + 20 = 666.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212863227) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 38145 + ... + 62295.

Almost surely, 2^1212863220 is an apocalyptic number.

1212863220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1212863220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1963847424).

1212863220 is an abundant number, since it is smaller than the sum of its proper divisors (2714831628).

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

1212863220 is a wasteful number, since it uses less digits than its factorization.

1212863220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24203 (or 24192 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1212863220 is about 34826.1858376711. The cubic root of 1212863220 is about 1066.4420853143.

The spelling of 1212863220 in words is "one billion, two hundred twelve million, eight hundred sixty-three thousand, two hundred twenty".