21598941 has 32 divisors (see below), whose sum is σ = 36053248. Its totient is φ = 11197440.

The previous prime is 21598921. The next prime is 21598963. The reversal of 21598941 is 14989512.

It is not a de Polignac number, because 21598941 - 2¹³ = 21590749 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 21598941.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21598901) 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 31 ways as a sum of consecutive naturals, for example, 16005 + ... + 17301.

It is an arithmetic number, because the mean of its divisors is an integer number (1126664).

Almost surely, 2^21598941 is an apocalyptic number.

21598941 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21598941 is a deficient number, since it is larger than the sum of its proper divisors (14454307).

21598941 is a wasteful number, since it uses less digits than its factorization.

21598941 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1381.

The product of its digits is 25920, while the sum is 39.

The square root of 21598941 is about 4647.4660837923. The cubic root of 21598941 is about 278.4907786067.

The spelling of 21598941 in words is "twenty-one million, five hundred ninety-eight thousand, nine hundred forty-one".