21500141 has 8 divisors (see below), whose sum is σ = 23367960. Its totient is φ = 19662912.

The previous prime is 21500137. The next prime is 21500161. The reversal of 21500141 is 14100512.

It can be written as a sum of positive squares in 4 ways, for example, as 5929225 + 15570916 = 2435^2 + 3946^2 .

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 21500141 - 2² = 21500137 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21500111) 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, 6170 + ... + 9003.

It is an arithmetic number, because the mean of its divisors is an integer number (2920995).

Almost surely, 2^21500141 is an apocalyptic number.

It is an amenable number.

21500141 is a deficient number, since it is larger than the sum of its proper divisors (1867819).

21500141 is a wasteful number, since it uses less digits than its factorization.

21500141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15295.

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 21500141 is about 4636.8244521439. The cubic root of 21500141 is about 278.0654961875.

Adding to 21500141 its reverse (14100512), we get a palindrome (35600653).

The spelling of 21500141 in words is "twenty-one million, five hundred thousand, one hundred forty-one".