21150613 has 4 divisors (see below), whose sum is σ = 23073408. Its totient is φ = 19227820.

The previous prime is 21150607. The next prime is 21150631. The reversal of 21150613 is 31605112.

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 21150613 - 2¹⁷ = 21019541 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 (21150653) 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 in 3 ways as a sum of consecutive naturals, for example, 961381 + ... + 961402.

It is an arithmetic number, because the mean of its divisors is an integer number (5768352).

Almost surely, 2^21150613 is an apocalyptic number.

It is an amenable number.

21150613 is a deficient number, since it is larger than the sum of its proper divisors (1922795).

21150613 is a wasteful number, since it uses less digits than its factorization.

21150613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1922794.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 21150613 is about 4598.9795607287. The cubic root of 21150613 is about 276.5504182514.

Adding to 21150613 its reverse (31605112), we get a palindrome (52755725).

The spelling of 21150613 in words is "twenty-one million, one hundred fifty thousand, six hundred thirteen".