21927061 has 4 divisors (see below), whose sum is σ = 23613772. Its totient is φ = 20240352.

The previous prime is 21927053. The next prime is 21927067. The reversal of 21927061 is 16072912.

It is a happy number.

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 4704561 + 17222500 = 2169^2 + 4150^2 .

It is a cyclic number.

It is not a de Polignac number, because 21927061 - 2³ = 21927053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21927067) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 843336 + ... + 843361.

It is an arithmetic number, because the mean of its divisors is an integer number (5903443).

Almost surely, 2^21927061 is an apocalyptic number.

It is an amenable number.

21927061 is a deficient number, since it is larger than the sum of its proper divisors (1686711).

21927061 is a wasteful number, since it uses less digits than its factorization.

21927061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1686710.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21927061 is about 4682.6339809983. The cubic root of 21927061 is about 279.8939266577.

Adding to 21927061 its reverse (16072912), we get a palindrome (37999973).

The spelling of 21927061 in words is "twenty-one million, nine hundred twenty-seven thousand, sixty-one".