21211054747 has 2 divisors, whose sum is σ = 21211054748. Its totient is φ = 21211054746.

The previous prime is 21211054741. The next prime is 21211054783. The reversal of 21211054747 is 74745011212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211054747 is a prime.

It is a super-3 number, since 3×21211054747³ (a number of 32 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (21211054741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605527373 + 10605527374.

It is an arithmetic number, because the mean of its divisors is an integer number (10605527374).

Almost surely, 2^21211054747 is an apocalyptic number.

21211054747 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211054747 is an equidigital number, since it uses as much as digits as its factorization.

21211054747 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15680, while the sum is 34.

Adding to 21211054747 its reverse (74745011212), we get a palindrome (95956065959).

The spelling of 21211054747 in words is "twenty-one billion, two hundred eleven million, fifty-four thousand, seven hundred forty-seven".