21081062 has 4 divisors (see below), whose sum is σ = 31621596. Its totient is φ = 10540530.

The previous prime is 21081061. The next prime is 21081101. The reversal of 21081062 is 26018012.

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

It is a super-2 number, since 2×21081062² = 888822350095688, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21081061) 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 as a sum of consecutive naturals, namely, 5270264 + ... + 5270267.

It is an arithmetic number, because the mean of its divisors is an integer number (7905399).

Almost surely, 2^21081062 is an apocalyptic number.

21081062 is a deficient number, since it is larger than the sum of its proper divisors (10540534).

21081062 is a wasteful number, since it uses less digits than its factorization.

21081062 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10540533.

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 21081062 is about 4591.4117654595. The cubic root of 21081062 is about 276.2469521855.

Adding to 21081062 its reverse (26018012), we get a palindrome (47099074).

The spelling of 21081062 in words is "twenty-one million, eighty-one thousand, sixty-two".