6721381953 has 96 divisors (see below), whose sum is σ = 12130110720. Its totient is φ = 3535695360.

The previous prime is 6721381949. The next prime is 6721381973. The reversal of 6721381953 is 3591831276.

It is not a de Polignac number, because 6721381953 - 2² = 6721381949 is a prime.

It is a super-2 number, since 2×6721381953² = 90353950716228188418, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6721381899 and 6721381908.

It is not an unprimeable number, because it can be changed into a prime (6721381903) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6322500 + ... + 6323562.

It is an arithmetic number, because the mean of its divisors is an integer number (126355320).

Almost surely, 2^6721381953 is an apocalyptic number.

It is an amenable number.

6721381953 is a deficient number, since it is larger than the sum of its proper divisors (5408728767).

6721381953 is a wasteful number, since it uses less digits than its factorization.

6721381953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1144 (or 1107 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 6721381953 is about 81984.0347445769. The cubic root of 6721381953 is about 1887.2069410251.

The spelling of 6721381953 in words is "six billion, seven hundred twenty-one million, three hundred eighty-one thousand, nine hundred fifty-three".