21598051 has 8 divisors (see below), whose sum is σ = 22181184. Its totient is φ = 21020160.

The previous prime is 21598043. The next prime is 21598061. The reversal of 21598051 is 15089512.

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 21598051 - 2³ = 21598043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21598061) 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, 7881 + ... + 10261.

It is an arithmetic number, because the mean of its divisors is an integer number (2772648).

Almost surely, 2^21598051 is an apocalyptic number.

21598051 is a deficient number, since it is larger than the sum of its proper divisors (583133).

21598051 is a wasteful number, since it uses less digits than its factorization.

21598051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2621.

The product of its (nonzero) digits is 3600, while the sum is 31.

The square root of 21598051 is about 4647.3703317037. The cubic root of 21598051 is about 278.4869534161.

The spelling of 21598051 in words is "twenty-one million, five hundred ninety-eight thousand, fifty-one".