21021307386 has 8 divisors (see below), whose sum is σ = 42042614784. Its totient is φ = 7007102460.

The previous prime is 21021307369. The next prime is 21021307387. The reversal of 21021307386 is 68370312012.

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

21021307386 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21021307387) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1751775610 + ... + 1751775621.

It is an arithmetic number, because the mean of its divisors is an integer number (5255326848).

Almost surely, 2^21021307386 is an apocalyptic number.

21021307386 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21021307386 is a wasteful number, since it uses less digits than its factorization.

21021307386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3503551236.

The product of its (nonzero) digits is 12096, while the sum is 33.

Adding to 21021307386 its reverse (68370312012), we get a palindrome (89391619398).

The spelling of 21021307386 in words is "twenty-one billion, twenty-one million, three hundred seven thousand, three hundred eighty-six".