71421421 has 4 divisors (see below), whose sum is σ = 71633692. Its totient is φ = 71209152.

The previous prime is 71421419. The next prime is 71421439. The reversal of 71421421 is 12412417.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12412417 = 443 ⋅28019.

It can be written as a sum of positive squares in 2 ways, for example, as 42380100 + 29041321 = 6510^2 + 5389^2 .

It is a cyclic number.

It is not a de Polignac number, because 71421421 - 2¹ = 71421419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71421392 and 71421401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71421481) 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, 105630 + ... + 106303.

It is an arithmetic number, because the mean of its divisors is an integer number (17908423).

Almost surely, 2^71421421 is an apocalyptic number.

It is an amenable number.

71421421 is a deficient number, since it is larger than the sum of its proper divisors (212271).

71421421 is a wasteful number, since it uses less digits than its factorization.

71421421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212270.

The product of its digits is 448, while the sum is 22.

The square root of 71421421 is about 8451.1195116387. The cubic root of 71421421 is about 414.8994211186.

Adding to 71421421 its reverse (12412417), we get a palindrome (83833838).

The spelling of 71421421 in words is "seventy-one million, four hundred twenty-one thousand, four hundred twenty-one".