21013954 has 8 divisors (see below), whose sum is σ = 33945660. Its totient is φ = 9698736.

The previous prime is 21013933. The next prime is 21013961. The reversal of 21013954 is 45931012.

It can be written as a sum of positive squares in 2 ways, for example, as 20948929 + 65025 = 4577^2 + 255^2 .

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

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, 404089 + ... + 404140.

Almost surely, 2^21013954 is an apocalyptic number.

21013954 is a deficient number, since it is larger than the sum of its proper divisors (12931706).

21013954 is a wasteful number, since it uses less digits than its factorization.

21013954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808244.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 21013954 is about 4584.0979483427. The cubic root of 21013954 is about 275.9535120891.

Adding to 21013954 its reverse (45931012), we get a palindrome (66944966).

The spelling of 21013954 in words is "twenty-one million, thirteen thousand, nine hundred fifty-four".