21601129 has 8 divisors (see below), whose sum is σ = 23635872. Its totient is φ = 19578240.

The previous prime is 21601121. The next prime is 21601171. The reversal of 21601129 is 92110612.

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

It is not a de Polignac number, because 21601129 - 2³ = 21601121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21601121) 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, 1102 + ... + 6664.

It is an arithmetic number, because the mean of its divisors is an integer number (2954484).

Almost surely, 2^21601129 is an apocalyptic number.

It is an amenable number.

21601129 is a deficient number, since it is larger than the sum of its proper divisors (2034743).

21601129 is a wasteful number, since it uses less digits than its factorization.

21601129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5927.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 21601129 is about 4647.7014749228. The cubic root of 21601129 is about 278.5001821117.

The spelling of 21601129 in words is "twenty-one million, six hundred one thousand, one hundred twenty-nine".