21054791 has 2 divisors, whose sum is σ = 21054792. Its totient is φ = 21054790.

The previous prime is 21054779. The next prime is 21054811. The reversal of 21054791 is 19745012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21054791 - 2¹⁸ = 20792647 is a prime.

It is a super-3 number, since 3×21054791³ (a number of 23 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21057791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10527395 + 10527396.

It is an arithmetic number, because the mean of its divisors is an integer number (10527396).

Almost surely, 2^21054791 is an apocalyptic number.

21054791 is a deficient number, since it is larger than the sum of its proper divisors (1).

21054791 is an equidigital number, since it uses as much as digits as its factorization.

21054791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 21054791 is about 4588.5499888309. The cubic root of 21054791 is about 276.1321524595.

The spelling of 21054791 in words is "twenty-one million, fifty-four thousand, seven hundred ninety-one".