21062121 has 4 divisors (see below), whose sum is σ = 28082832. Its totient is φ = 14041412.

The previous prime is 21062101. The next prime is 21062137. The reversal of 21062121 is 12126012.

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 21062121 - 2⁶ = 21062057 is a prime.

It is a super-2 number, since 2×21062121² = 887225882037282, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21062121.

It is not an unprimeable number, because it can be changed into a prime (21062101) 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, 3510351 + ... + 3510356.

It is an arithmetic number, because the mean of its divisors is an integer number (7020708).

Almost surely, 2^21062121 is an apocalyptic number.

It is an amenable number.

21062121 is a deficient number, since it is larger than the sum of its proper divisors (7020711).

21062121 is an equidigital number, since it uses as much as digits as its factorization.

21062121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7020710.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 21062121 is about 4589.3486465946. The cubic root of 21062121 is about 276.1641928922.

Adding to 21062121 its reverse (12126012), we get a palindrome (33188133).

The spelling of 21062121 in words is "twenty-one million, sixty-two thousand, one hundred twenty-one".