21180135 has 8 divisors (see below), whose sum is σ = 33888240. Its totient is φ = 11296064.

The previous prime is 21180101. The next prime is 21180139. The reversal of 21180135 is 53108112.

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 21180135 - 2¹⁰ = 21179111 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21180139) 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, 705990 + ... + 706019.

It is an arithmetic number, because the mean of its divisors is an integer number (4236030).

Almost surely, 2^21180135 is an apocalyptic number.

21180135 is a deficient number, since it is larger than the sum of its proper divisors (12708105).

21180135 is a wasteful number, since it uses less digits than its factorization.

21180135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412017.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 21180135 is about 4602.1880665614. The cubic root of 21180135 is about 276.6790280117.

Adding to 21180135 its reverse (53108112), we get a palindrome (74288247).

The spelling of 21180135 in words is "twenty-one million, one hundred eighty thousand, one hundred thirty-five".