1213133021 has 4 divisors (see below), whose sum is σ = 1231239552. Its totient is φ = 1195026492.

The previous prime is 1213132993. The next prime is 1213133029. The reversal of 1213133021 is 1203313121.

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 1213133021 - 2¹⁴ = 1213116637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213133029) 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, 9053165 + ... + 9053298.

It is an arithmetic number, because the mean of its divisors is an integer number (307809888).

Almost surely, 2^1213133021 is an apocalyptic number.

It is an amenable number.

1213133021 is a deficient number, since it is larger than the sum of its proper divisors (18106531).

1213133021 is an equidigital number, since it uses as much as digits as its factorization.

1213133021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18106530.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 1213133021 is about 34830.0591587209. The cubic root of 1213133021 is about 1066.5211560081.

Adding to 1213133021 its reverse (1203313121), we get a palindrome (2416446142).

The spelling of 1213133021 in words is "one billion, two hundred thirteen million, one hundred thirty-three thousand, twenty-one".