8261721063 has 32 divisors (see below), whose sum is σ = 12365337600. Its totient is φ = 5451451200.

The previous prime is 8261721029. The next prime is 8261721067. The reversal of 8261721063 is 3601271628.

It is a de Polignac number, because none of the positive numbers 2^k-8261721063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8261721067) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1443778 + ... + 1449488.

It is an arithmetic number, because the mean of its divisors is an integer number (386416800).

Almost surely, 2^8261721063 is an apocalyptic number.

8261721063 is a deficient number, since it is larger than the sum of its proper divisors (4103616537).

8261721063 is a wasteful number, since it uses less digits than its factorization.

8261721063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6260 (or 6254 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 8261721063 is about 90894.0100501678. The cubic root of 8261721063 is about 2021.5764792866.

The spelling of 8261721063 in words is "eight billion, two hundred sixty-one million, seven hundred twenty-one thousand, sixty-three".