1212042420 has 192 divisors, whose sum is σ = 3874106880. Its totient is φ = 314496000.

The previous prime is 1212042401. The next prime is 1212042463. The reversal of 1212042420 is 242402121.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1212042393 and 1212042402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3872184 + ... + 3872496.

It is an arithmetic number, because the mean of its divisors is an integer number (20177640).

Almost surely, 2^1212042420 is an apocalyptic number.

1212042420 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 1212042420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1937053440).

1212042420 is an abundant number, since it is smaller than the sum of its proper divisors (2662064460).

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

1212042420 is a wasteful number, since it uses less digits than its factorization.

1212042420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503 (or 495 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 1212042420 is about 34814.3996070591. The cubic root of 1212042420 is about 1066.2014609847.

Adding to 1212042420 its reverse (242402121), we get a palindrome (1454444541).

The spelling of 1212042420 in words is "one billion, two hundred twelve million, forty-two thousand, four hundred twenty".