1220400500 has 48 divisors (see below), whose sum is σ = 2907672768. Its totient is φ = 443780000.

The previous prime is 1220400499. The next prime is 1220400551. The reversal of 1220400500 is 50040221.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105446 + ... + 116445.

It is an arithmetic number, because the mean of its divisors is an integer number (60576516).

Almost surely, 2^1220400500 is an apocalyptic number.

1220400500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1220400500 is an abundant number, since it is smaller than the sum of its proper divisors (1687272268).

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

1220400500 is a wasteful number, since it uses less digits than its factorization.

1220400500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221921 (or 221909 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 14.

The square root of 1220400500 is about 34934.2310635285. The cubic root of 1220400500 is about 1068.6466425360.

Adding to 1220400500 its reverse (50040221), we get a palindrome (1270440721).

The spelling of 1220400500 in words is "one billion, two hundred twenty million, four hundred thousand, five hundred".