71631421 has 32 divisors (see below), whose sum is σ = 83635200. Its totient is φ = 60963840.

The previous prime is 71631401. The next prime is 71631449. The reversal of 71631421 is 12413617.

It is a 5-Lehmer number, since φ(71631421) divides (71631421-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 71631421 - 2¹⁹ = 71107133 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 (71631401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 657115 + ... + 657223.

It is an arithmetic number, because the mean of its divisors is an integer number (2613600).

Almost surely, 2^71631421 is an apocalyptic number.

It is an amenable number.

71631421 is a deficient number, since it is larger than the sum of its proper divisors (12003779).

71631421 is a wasteful number, since it uses less digits than its factorization.

71631421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 229.

The product of its digits is 1008, while the sum is 25.

The square root of 71631421 is about 8463.5347816382. The cubic root of 71631421 is about 415.3056653592.

The spelling of 71631421 in words is "seventy-one million, six hundred thirty-one thousand, four hundred twenty-one".