80021971 has 2 divisors, whose sum is σ = 80021972. Its totient is φ = 80021970.

The previous prime is 80021959. The next prime is 80021999. The reversal of 80021971 is 17912008.

It is an a-pointer prime, because the next prime (80021999) can be obtained adding 80021971 to its sum of digits (28).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 80021971 - 2²⁵ = 46467539 is a prime.

It is a Chen prime.

It is the 8946-th Hogben number.

It is not a weakly prime, because it can be changed into another prime (80021171) by changing a digit.

It is a nontrivial repunit in base 8945.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40010985 + 40010986.

It is an arithmetic number, because the mean of its divisors is an integer number (40010986).

Almost surely, 2^80021971 is an apocalyptic number.

80021971 is a deficient number, since it is larger than the sum of its proper divisors (1).

80021971 is an equidigital number, since it uses as much as digits as its factorization.

80021971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 80021971 is about 8945.5000419205. The cubic root of 80021971 is about 430.9263802996.

Adding to 80021971 its reverse (17912008), we get a palindrome (97933979).

The spelling of 80021971 in words is "eighty million, twenty-one thousand, nine hundred seventy-one".