21380869 has 8 divisors (see below), whose sum is σ = 22626432. Its totient is φ = 20161680.

The previous prime is 21380867. The next prime is 21380881. The reversal of 21380869 is 96808312.

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 21380869 - 2¹ = 21380867 is a prime.

It is a super-2 number, since 2×21380869² = 914283118390322, 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 (21380867) 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, 4914 + ... + 8179.

It is an arithmetic number, because the mean of its divisors is an integer number (2828304).

Almost surely, 2^21380869 is an apocalyptic number.

It is an amenable number.

21380869 is a deficient number, since it is larger than the sum of its proper divisors (1245563).

21380869 is a wasteful number, since it uses less digits than its factorization.

21380869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13187.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 21380869 is about 4623.9451770106. The cubic root of 21380869 is about 277.5503531169.

The spelling of 21380869 in words is "twenty-one million, three hundred eighty thousand, eight hundred sixty-nine".