1221022051 has 4 divisors (see below), whose sum is σ = 1241717400. Its totient is φ = 1200326704.

The previous prime is 1221022037. The next prime is 1221022057. The reversal of 1221022051 is 1502201221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221022051 - 2¹⁹ = 1220497763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221022057) 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, 10347586 + ... + 10347703.

It is an arithmetic number, because the mean of its divisors is an integer number (310429350).

Almost surely, 2^1221022051 is an apocalyptic number.

1221022051 is a deficient number, since it is larger than the sum of its proper divisors (20695349).

1221022051 is an equidigital number, since it uses as much as digits as its factorization.

1221022051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20695348.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 1221022051 is about 34943.1259477454. The cubic root of 1221022051 is about 1068.8280326231.

Adding to 1221022051 its reverse (1502201221), we get a palindrome (2723223272).

The spelling of 1221022051 in words is "one billion, two hundred twenty-one million, twenty-two thousand, fifty-one".