1221257130 has 16 divisors (see below), whose sum is σ = 2931017184. Its totient is φ = 325668560.

The previous prime is 1221257087. The next prime is 1221257159. The reversal of 1221257130 is 317521221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221257130.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20354256 + ... + 20354315.

It is an arithmetic number, because the mean of its divisors is an integer number (183188574).

Almost surely, 2^1221257130 is an apocalyptic number.

1221257130 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221257130 is an abundant number, since it is smaller than the sum of its proper divisors (1709760054).

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

1221257130 is a wasteful number, since it uses less digits than its factorization.

1221257130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40708581.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 1221257130 is about 34946.4895232697. The cubic root of 1221257130 is about 1068.8966207653.

Adding to 1221257130 its reverse (317521221), we get a palindrome (1538778351).

The spelling of 1221257130 in words is "one billion, two hundred twenty-one million, two hundred fifty-seven thousand, one hundred thirty".