1221200125 has 16 divisors (see below), whose sum is σ = 1525784832. Its totient is φ = 975853200.

The previous prime is 1221200119. The next prime is 1221200159. The reversal of 1221200125 is 5210021221.

It is a happy number.

It is not a de Polignac number, because 1221200125 - 2⁵ = 1221200093 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221200099 and 1221200108.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115824 + ... + 125926.

It is an arithmetic number, because the mean of its divisors is an integer number (95361552).

Almost surely, 2^1221200125 is an apocalyptic number.

It is an amenable number.

1221200125 is a deficient number, since it is larger than the sum of its proper divisors (304584707).

1221200125 is an equidigital number, since it uses as much as digits as its factorization.

1221200125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11085 (or 11075 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 1221200125 is about 34945.6739096558. The cubic root of 1221200125 is about 1068.8799894328.

Adding to 1221200125 its reverse (5210021221), we get a palindrome (6431221346).

The spelling of 1221200125 in words is "one billion, two hundred twenty-one million, two hundred thousand, one hundred twenty-five".