1221503125 has 24 divisors (see below), whose sum is σ = 1616662152. Its totient is φ = 919680000.

The previous prime is 1221503123. The next prime is 1221503131. The reversal of 1221503125 is 5213051221.

It can be written as a sum of positive squares in 12 ways, for example, as 1070729284 + 150773841 = 32722^2 + 12279^2 .

It is not a de Polignac number, because 1221503125 - 2¹ = 1221503123 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221503096 and 1221503105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221503123) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41629 + ... + 64621.

It is an arithmetic number, because the mean of its divisors is an integer number (67360923).

Almost surely, 2^1221503125 is an apocalyptic number.

It is an amenable number.

1221503125 is a deficient number, since it is larger than the sum of its proper divisors (395159027).

1221503125 is an frugal number, since it uses more digits than its factorization.

1221503125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23035 (or 23015 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 1221503125 is about 34950.0089413436. The cubic root of 1221503125 is about 1068.9683844054.

Adding to 1221503125 its reverse (5213051221), we get a palindrome (6434554346).

The spelling of 1221503125 in words is "one billion, two hundred twenty-one million, five hundred three thousand, one hundred twenty-five".