21513101 has 8 divisors (see below), whose sum is σ = 22430208. Its totient is φ = 20610000.

The previous prime is 21513091. The next prime is 21513113. The reversal of 21513101 is 10131512.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21513101 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 (21513161) 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, 305 + ... + 6566.

It is an arithmetic number, because the mean of its divisors is an integer number (2803776).

Almost surely, 2^21513101 is an apocalyptic number.

It is an amenable number.

21513101 is a deficient number, since it is larger than the sum of its proper divisors (917107).

21513101 is a wasteful number, since it uses less digits than its factorization.

21513101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7003.

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 21513101 is about 4638.2217497657. The cubic root of 21513101 is about 278.1213563635.

Adding to 21513101 its reverse (10131512), we get a palindrome (31644613).

The spelling of 21513101 in words is "twenty-one million, five hundred thirteen thousand, one hundred one".