1200011021 has 4 divisors (see below), whose sum is σ = 1309102944. Its totient is φ = 1090919100.

The previous prime is 1200011017. The next prime is 1200011051. The reversal of 1200011021 is 1201100021.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1201100021 = 11 ⋅109190911.

It is a cyclic number.

It is not a de Polignac number, because 1200011021 - 2² = 1200011017 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 (1200011051) 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, 54545945 + ... + 54545966.

It is an arithmetic number, because the mean of its divisors is an integer number (327275736).

Almost surely, 2^1200011021 is an apocalyptic number.

1200011021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1200011021 is a deficient number, since it is larger than the sum of its proper divisors (109091923).

1200011021 is a wasteful number, since it uses less digits than its factorization.

1200011021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109091922.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1200011021 is about 34641.1752254452. The cubic root of 1200011021 is about 1062.6618223838.

Adding to 1200011021 its reverse (1201100021), we get a palindrome (2401111042).

The spelling of 1200011021 in words is "one billion, two hundred million, eleven thousand, twenty-one".