21221201471 has 2 divisors, whose sum is σ = 21221201472. Its totient is φ = 21221201470.

The previous prime is 21221201447. The next prime is 21221201503. The reversal of 21221201471 is 17410212212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21221201471 - 2²⁶ = 21154092607 is a prime.

It is a super-3 number, since 3×21221201471³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221201411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610600735 + 10610600736.

It is an arithmetic number, because the mean of its divisors is an integer number (10610600736).

Almost surely, 2^21221201471 is an apocalyptic number.

21221201471 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221201471 is an equidigital number, since it uses as much as digits as its factorization.

21221201471 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 448, while the sum is 23.

Adding to 21221201471 its reverse (17410212212), we get a palindrome (38631413683).

The spelling of 21221201471 in words is "twenty-one billion, two hundred twenty-one million, two hundred one thousand, four hundred seventy-one".