21851069 has 8 divisors (see below), whose sum is σ = 23184000. Its totient is φ = 20523456.

The previous prime is 21851057. The next prime is 21851077. The reversal of 21851069 is 96015812.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21851069 is a prime.

It is a super-2 number, since 2×21851069² = 954938432885522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21851029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9932 + ... + 11930.

It is an arithmetic number, because the mean of its divisors is an integer number (2898000).

Almost surely, 2^21851069 is an apocalyptic number.

It is an amenable number.

21851069 is a deficient number, since it is larger than the sum of its proper divisors (1332931).

21851069 is a wasteful number, since it uses less digits than its factorization.

21851069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2659.

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 21851069 is about 4674.5127018760. The cubic root of 21851069 is about 279.5702122307.

The spelling of 21851069 in words is "twenty-one million, eight hundred fifty-one thousand, sixty-nine".