21513701 has 8 divisors (see below), whose sum is σ = 23868000. Its totient is φ = 19225840.

The previous prime is 21513697. The next prime is 21513749. The reversal of 21513701 is 10731512.

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

It is a cyclic number.

It is not a de Polignac number, because 21513701 - 2² = 21513697 is a prime.

It is a super-3 number, since 3×21513701³ (a number of 23 digits) contains 333 as substring.

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 (21513001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15926 + ... + 17223.

It is an arithmetic number, because the mean of its divisors is an integer number (2983500).

Almost surely, 2^21513701 is an apocalyptic number.

It is an amenable number.

21513701 is a deficient number, since it is larger than the sum of its proper divisors (2354299).

21513701 is a wasteful number, since it uses less digits than its factorization.

21513701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33219.

The product of its (nonzero) digits is 210, while the sum is 20.

The square root of 21513701 is about 4638.2864292754. The cubic root of 21513701 is about 278.1239419393.

The spelling of 21513701 in words is "twenty-one million, five hundred thirteen thousand, seven hundred one".