71204021 has 16 divisors (see below), whose sum is σ = 87216384. Its totient is φ = 56795904.

The previous prime is 71204009. The next prime is 71204051. The reversal of 71204021 is 12040217.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71204021 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 (71204051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20 + ... + 11933.

It is an arithmetic number, because the mean of its divisors is an integer number (5451024).

Almost surely, 2^71204021 is an apocalyptic number.

It is an amenable number.

71204021 is a deficient number, since it is larger than the sum of its proper divisors (16012363).

71204021 is a wasteful number, since it uses less digits than its factorization.

71204021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12020.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 71204021 is about 8438.2475076286. The cubic root of 71204021 is about 414.4780218281.

Adding to 71204021 its reverse (12040217), we get a palindrome (83244238).

The spelling of 71204021 in words is "seventy-one million, two hundred four thousand, twenty-one".