21088053 has 16 divisors (see below), whose sum is σ = 35704960. Its totient is φ = 12050208.

The previous prime is 21088013. The next prime is 21088057. The reversal of 21088053 is 35088012.

It is a happy number.

It is not a de Polignac number, because 21088053 - 2¹⁶ = 21022517 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21088057) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55600 + ... + 55977.

It is an arithmetic number, because the mean of its divisors is an integer number (2231560).

Almost surely, 2^21088053 is an apocalyptic number.

It is an amenable number.

21088053 is a deficient number, since it is larger than the sum of its proper divisors (14616907).

21088053 is a wasteful number, since it uses less digits than its factorization.

21088053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111593 (or 111587 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 21088053 is about 4592.1730150333. The cubic root of 21088053 is about 276.2774855776.

The spelling of 21088053 in words is "twenty-one million, eighty-eight thousand, fifty-three".