1221012133 has 16 divisors (see below), whose sum is σ = 1365484032. Its totient is φ = 1082214000.

The previous prime is 1221012119. The next prime is 1221012137. The reversal of 1221012133 is 3312101221.

It is a cyclic number.

It is not a de Polignac number, because 1221012133 - 2²¹ = 1218914981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221012137) 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, 296418 + ... + 300508.

It is an arithmetic number, because the mean of its divisors is an integer number (85342752).

Almost surely, 2^1221012133 is an apocalyptic number.

It is an amenable number.

1221012133 is a deficient number, since it is larger than the sum of its proper divisors (144471899).

1221012133 is a wasteful number, since it uses less digits than its factorization.

1221012133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4776.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1221012133 is about 34942.9840311328. The cubic root of 1221012133 is about 1068.8251386909.

Adding to 1221012133 its reverse (3312101221), we get a palindrome (4533113354).

The spelling of 1221012133 in words is "one billion, two hundred twenty-one million, twelve thousand, one hundred thirty-three".