1221420211 has 8 divisors (see below), whose sum is σ = 1332721584. Its totient is φ = 1110162720.

The previous prime is 1221420127. The next prime is 1221420227. The reversal of 1221420211 is 1120241221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221420211 - 2¹³ = 1221412019 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221420271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80265 + ... + 94261.

It is an arithmetic number, because the mean of its divisors is an integer number (166590198).

Almost surely, 2^1221420211 is an apocalyptic number.

1221420211 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221420211 is a deficient number, since it is larger than the sum of its proper divisors (111301373).

1221420211 is a wasteful number, since it uses less digits than its factorization.

1221420211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21941.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 1221420211 is about 34948.8227412598. The cubic root of 1221420211 is about 1068.9441971429.

Adding to 1221420211 its reverse (1120241221), we get a palindrome (2341661432).

The spelling of 1221420211 in words is "one billion, two hundred twenty-one million, four hundred twenty thousand, two hundred eleven".