21858051 has 8 divisors (see below), whose sum is σ = 29165760. Its totient is φ = 14561192.

The previous prime is 21858029. The next prime is 21858127. The reversal of 21858051 is 15085812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21858051 - 2⁵ = 21858019 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21850051) 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 7 ways as a sum of consecutive naturals, for example, 5896 + ... + 8858.

It is an arithmetic number, because the mean of its divisors is an integer number (3645720).

Almost surely, 2^21858051 is an apocalyptic number.

21858051 is a deficient number, since it is larger than the sum of its proper divisors (7307709).

21858051 is a wasteful number, since it uses less digits than its factorization.

21858051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5425.

The product of its (nonzero) digits is 3200, while the sum is 30.

The square root of 21858051 is about 4675.2594580408. The cubic root of 21858051 is about 279.5999857757.

The spelling of 21858051 in words is "twenty-one million, eight hundred fifty-eight thousand, fifty-one".