21540126 has 8 divisors (see below), whose sum is σ = 43080264. Its totient is φ = 7180040.

The previous prime is 21540083. The next prime is 21540157. The reversal of 21540126 is 62104512.

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

21540126 is an admirable number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1795005 + ... + 1795016.

It is an arithmetic number, because the mean of its divisors is an integer number (5385033).

Almost surely, 2^21540126 is an apocalyptic number.

21540126 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21540126 is a wasteful number, since it uses less digits than its factorization.

21540126 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3590026.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 21540126 is about 4641.1341286371. The cubic root of 21540126 is about 278.2377673592.

Adding to 21540126 its reverse (62104512), we get a palindrome (83644638).

The spelling of 21540126 in words is "twenty-one million, five hundred forty thousand, one hundred twenty-six".