1221012253 has 4 divisors (see below), whose sum is σ = 1235723328. Its totient is φ = 1206301180.

The previous prime is 1221012241. The next prime is 1221012277. The reversal of 1221012253 is 3522101221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1221012253 - 2¹³ = 1221004061 is a prime.

It is a super-2 number, since 2×1221012253² = 2981741843952272018, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221012253.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221015253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7355413 + ... + 7355578.

It is an arithmetic number, because the mean of its divisors is an integer number (308930832).

Almost surely, 2^1221012253 is an apocalyptic number.

It is an amenable number.

1221012253 is a deficient number, since it is larger than the sum of its proper divisors (14711075).

1221012253 is an equidigital number, since it uses as much as digits as its factorization.

1221012253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14711074.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 1221012253 is about 34942.9857482156. The cubic root of 1221012253 is about 1068.8251737053.

Adding to 1221012253 its reverse (3522101221), we get a palindrome (4743113474).

The spelling of 1221012253 in words is "one billion, two hundred twenty-one million, twelve thousand, two hundred fifty-three".