21354053 has 12 divisors (see below), whose sum is σ = 25029612. Its totient is φ = 18164160.

The previous prime is 21354049. The next prime is 21354059. The reversal of 21354053 is 35045312.

It can be written as a sum of positive squares in 2 ways, for example, as 6315169 + 15038884 = 2513^2 + 3878^2 .

It is not a de Polignac number, because 21354053 - 2² = 21354049 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 (21354059) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5123 + ... + 8303.

It is an arithmetic number, because the mean of its divisors is an integer number (2085801).

Almost surely, 2^21354053 is an apocalyptic number.

It is an amenable number.

21354053 is a deficient number, since it is larger than the sum of its proper divisors (3675559).

21354053 is a wasteful number, since it uses less digits than its factorization.

21354053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3332 (or 3325 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 21354053 is about 4621.0445788804. The cubic root of 21354053 is about 277.4342695278.

Adding to 21354053 its reverse (35045312), we get a palindrome (56399365).

The spelling of 21354053 in words is "twenty-one million, three hundred fifty-four thousand, fifty-three".