21013053 has 8 divisors (see below), whose sum is σ = 29235648. Its totient is φ = 13399584.

The previous prime is 21013049. The next prime is 21013061. The reversal of 21013053 is 35031012.

It is a happy number.

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

It is not a de Polignac number, because 21013053 - 2² = 21013049 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21013043) 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, 152200 + ... + 152337.

It is an arithmetic number, because the mean of its divisors is an integer number (3654456).

Almost surely, 2^21013053 is an apocalyptic number.

21013053 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21013053 is a deficient number, since it is larger than the sum of its proper divisors (8222595).

21013053 is a wasteful number, since it uses less digits than its factorization.

21013053 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304563.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 21013053 is about 4583.9996727749. Note that the first 3 decimals coincide. The cubic root of 21013053 is about 275.9495680801.

Adding to 21013053 its reverse (35031012), we get a palindrome (56044065).

The spelling of 21013053 in words is "twenty-one million, thirteen thousand, fifty-three".