1220542400 has 168 divisors, whose sum is σ = 3744748416. Its totient is φ = 380390400.

The previous prime is 1220542397. The next prime is 1220542423. The reversal of 1220542400 is 42450221.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 118247 + ... + 128153.

Almost surely, 2^1220542400 is an apocalyptic number.

1220542400 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 1220542400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1872374208).

1220542400 is an abundant number, since it is smaller than the sum of its proper divisors (2524206016).

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

1220542400 is a wasteful number, since it uses less digits than its factorization.

1220542400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9947 (or 9932 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 1220542400 is about 34936.2619637534. The cubic root of 1220542400 is about 1068.6880592900.

Adding to 1220542400 its reverse (42450221), we get a palindrome (1262992621).

The spelling of 1220542400 in words is "one billion, two hundred twenty million, five hundred forty-two thousand, four hundred".