21701869 has 8 divisors (see below), whose sum is σ = 25472768. Its totient is φ = 18098640.

The previous prime is 21701839. The next prime is 21701873. The reversal of 21701869 is 96810712.

It is a happy number.

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

It is not a de Polignac number, because 21701869 - 2⁵ = 21701837 is a prime.

It is a super-2 number, since 2×21701869² = 941942236186322, 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 (21701839) 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 7 ways as a sum of consecutive naturals, for example, 41637 + ... + 42154.

It is an arithmetic number, because the mean of its divisors is an integer number (3184096).

Almost surely, 2^21701869 is an apocalyptic number.

It is an amenable number.

21701869 is a deficient number, since it is larger than the sum of its proper divisors (3770899).

21701869 is an equidigital number, since it uses as much as digits as its factorization.

21701869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83835.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 21701869 is about 4658.5264837715. The cubic root of 21701869 is about 278.9324528265.

The spelling of 21701869 in words is "twenty-one million, seven hundred one thousand, eight hundred sixty-nine".