21133767 has 4 divisors (see below), whose sum is σ = 28178360. Its totient is φ = 14089176.

The previous prime is 21133753. The next prime is 21133781. The reversal of 21133767 is 76733112.

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

It is an interprime number because it is at equal distance from previous prime (21133753) and next prime (21133781).

It is not a de Polignac number, because 21133767 - 2⁷ = 21133639 is a prime.

It is a super-2 number, since 2×21133767² = 893272215220578, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3522292 + ... + 3522297.

It is an arithmetic number, because the mean of its divisors is an integer number (7044590).

Almost surely, 2^21133767 is an apocalyptic number.

21133767 is a deficient number, since it is larger than the sum of its proper divisors (7044593).

21133767 is an equidigital number, since it uses as much as digits as its factorization.

21133767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7044592.

The product of its digits is 5292, while the sum is 30.

The square root of 21133767 is about 4597.1477026522. The cubic root of 21133767 is about 276.4769766328.

Adding to 21133767 its reverse (76733112), we get a palindrome (97866879).

The spelling of 21133767 in words is "twenty-one million, one hundred thirty-three thousand, seven hundred sixty-seven".