21071500063 has 4 divisors (see below), whose sum is σ = 21076303248. Its totient is φ = 21066696880.

The previous prime is 21071500057. The next prime is 21071500081. The reversal of 21071500063 is 36000517012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21071500063 - 2²¹ = 21069402911 is a prime.

It is a super-2 number, since 2×21071500063² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21071500033) 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, 2395006 + ... + 2403787.

It is an arithmetic number, because the mean of its divisors is an integer number (5269075812).

Almost surely, 2^21071500063 is an apocalyptic number.

21071500063 is a deficient number, since it is larger than the sum of its proper divisors (4803185).

21071500063 is an equidigital number, since it uses as much as digits as its factorization.

21071500063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4803184.

The product of its (nonzero) digits is 1260, while the sum is 25.

The spelling of 21071500063 in words is "twenty-one billion, seventy-one million, five hundred thousand, sixty-three".