1220042656 has 24 divisors (see below), whose sum is σ = 2745096480. Its totient is φ = 522875328.

The previous prime is 1220042653. The next prime is 1220042657. The reversal of 1220042656 is 6562400221.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (1220042653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2723086 + ... + 2723533.

It is an arithmetic number, because the mean of its divisors is an integer number (114379020).

Almost surely, 2^1220042656 is an apocalyptic number.

1220042656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1220042656 is an abundant number, since it is smaller than the sum of its proper divisors (1525053824).

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

1220042656 is an equidigital number, since it uses as much as digits as its factorization.

1220042656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5446636 (or 5446628 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 1220042656 is about 34929.1090066724. The cubic root of 1220042656 is about 1068.5421833382.

Adding to 1220042656 its reverse (6562400221), we get a palindrome (7782442877).

The spelling of 1220042656 in words is "one billion, two hundred twenty million, forty-two thousand, six hundred fifty-six".