21122701 has 4 divisors (see below), whose sum is σ = 21851100. Its totient is φ = 20394304.

The previous prime is 21122677. The next prime is 21122707. The reversal of 21122701 is 10722112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5904900 + 15217801 = 2430^2 + 3901^2 .

It is a cyclic number.

It is not a de Polignac number, because 21122701 - 2⁵ = 21122669 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 (21122707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364156 + ... + 364213.

It is an arithmetic number, because the mean of its divisors is an integer number (5462775).

Almost surely, 2^21122701 is an apocalyptic number.

It is an amenable number.

21122701 is a deficient number, since it is larger than the sum of its proper divisors (728399).

21122701 is an equidigital number, since it uses as much as digits as its factorization.

21122701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728398.

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 21122701 is about 4595.9439726785. The cubic root of 21122701 is about 276.4287121913.

Adding to 21122701 its reverse (10722112), we get a palindrome (31844813).

The spelling of 21122701 in words is "twenty-one million, one hundred twenty-two thousand, seven hundred one".