82021397 has 4 divisors (see below), whose sum is σ = 82410336. Its totient is φ = 81632460.

The previous prime is 82021351. The next prime is 82021399. The reversal of 82021397 is 79312028.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 82021397 - 2¹⁰ = 82020373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82021399) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194153 + ... + 194574.

It is an arithmetic number, because the mean of its divisors is an integer number (20602584).

Almost surely, 2^82021397 is an apocalyptic number.

It is an amenable number.

82021397 is a deficient number, since it is larger than the sum of its proper divisors (388939).

82021397 is a wasteful number, since it uses less digits than its factorization.

82021397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388938.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 82021397 is about 9056.5665127575. The cubic root of 82021397 is about 434.4859334492.

The spelling of 82021397 in words is "eighty-two million, twenty-one thousand, three hundred ninety-seven".