21065747347 has 8 divisors (see below), whose sum is σ = 21749824512. Its totient is φ = 20381953800.

The previous prime is 21065747309. The next prime is 21065747363. The reversal of 21065747347 is 74374756012.

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 21065747347 - 2¹¹ = 21065745299 is a prime.

It is a super-2 number, since 2×21065747347² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21065747297 and 21065747306.

It is not an unprimeable number, because it can be changed into a prime (21065717347) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85572 + ... + 222382.

It is an arithmetic number, because the mean of its divisors is an integer number (2718728064).

Almost surely, 2^21065747347 is an apocalyptic number.

21065747347 is a deficient number, since it is larger than the sum of its proper divisors (684077165).

21065747347 is a wasteful number, since it uses less digits than its factorization.

21065747347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141809.

The product of its (nonzero) digits is 987840, while the sum is 46.

The spelling of 21065747347 in words is "twenty-one billion, sixty-five million, seven hundred forty-seven thousand, three hundred forty-seven".