1221276025 has 6 divisors (see below), whose sum is σ = 1514382302. Its totient is φ = 977020800.

The previous prime is 1221276013. The next prime is 1221276037. The reversal of 1221276025 is 5206721221.

It is an interprime number because it is at equal distance from previous prime (1221276013) and next prime (1221276037).

It can be written as a sum of positive squares in 3 ways, for example, as 6335289 + 1214940736 = 2517^2 + 34856^2 .

It is not a de Polignac number, because 1221276025 - 2⁹ = 1221275513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221275984 and 1221276002.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 24425496 + ... + 24425545.

Almost surely, 2^1221276025 is an apocalyptic number.

It is an amenable number.

1221276025 is a deficient number, since it is larger than the sum of its proper divisors (293106277).

1221276025 is an equidigital number, since it uses as much as digits as its factorization.

1221276025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48851051 (or 48851046 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 1221276025 is about 34946.7598641133. The cubic root of 1221276025 is about 1068.9021333083.

Adding to 1221276025 its reverse (5206721221), we get a palindrome (6427997246).

The spelling of 1221276025 in words is "one billion, two hundred twenty-one million, two hundred seventy-six thousand, twenty-five".