1222556521 has 16 divisors (see below), whose sum is σ = 1271142400. Its totient is φ = 1174996368.

The previous prime is 1222556471. The next prime is 1222556537. The reversal of 1222556521 is 1256552221.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1222556521 - 2⁹ = 1222556009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1222556221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1653970 + ... + 1654708.

It is an arithmetic number, because the mean of its divisors is an integer number (79446400).

Almost surely, 2^1222556521 is an apocalyptic number.

It is an amenable number.

1222556521 is a deficient number, since it is larger than the sum of its proper divisors (48585879).

1222556521 is an equidigital number, since it uses as much as digits as its factorization.

1222556521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1348.

The product of its digits is 12000, while the sum is 31.

The square root of 1222556521 is about 34965.0757327937. The cubic root of 1222556521 is about 1069.2755806404.

The spelling of 1222556521 in words is "one billion, two hundred twenty-two million, five hundred fifty-six thousand, five hundred twenty-one".