1225612421 has 4 divisors (see below), whose sum is σ = 1337031744. Its totient is φ = 1114193100.

The previous prime is 1225612411. The next prime is 1225612483. The reversal of 1225612421 is 1242165221.

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 1225612421 - 2¹⁴ = 1225596037 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225612411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55709645 + ... + 55709666.

It is an arithmetic number, because the mean of its divisors is an integer number (334257936).

Almost surely, 2^1225612421 is an apocalyptic number.

1225612421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1225612421 is a deficient number, since it is larger than the sum of its proper divisors (111419323).

1225612421 is a wasteful number, since it uses less digits than its factorization.

1225612421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111419322.

The product of its digits is 1920, while the sum is 26.

The square root of 1225612421 is about 35008.7477782339. The cubic root of 1225612421 is about 1070.1657591048.

Adding to 1225612421 its reverse (1242165221), we get a palindrome (2467777642).

The spelling of 1225612421 in words is "one billion, two hundred twenty-five million, six hundred twelve thousand, four hundred twenty-one".