21539134 has 8 divisors (see below), whose sum is σ = 32443488. Its totient is φ = 10724640.

The previous prime is 21539107. The next prime is 21539137. The reversal of 21539134 is 43193512.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21539137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21862 + ... + 22825.

It is an arithmetic number, because the mean of its divisors is an integer number (4055436).

Almost surely, 2^21539134 is an apocalyptic number.

21539134 is a deficient number, since it is larger than the sum of its proper divisors (10904354).

21539134 is a wasteful number, since it uses less digits than its factorization.

21539134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44930.

The product of its digits is 3240, while the sum is 28.

The square root of 21539134 is about 4641.0272569766. The cubic root of 21539134 is about 278.2334960115.

The spelling of 21539134 in words is "twenty-one million, five hundred thirty-nine thousand, one hundred thirty-four".