71421905 has 16 divisors (see below), whose sum is σ = 87899904. Its totient is φ = 55685760.

The previous prime is 71421881. The next prime is 71421929. The reversal of 71421905 is 50912417.

It is an interprime number because it is at equal distance from previous prime (71421881) and next prime (71421929).

It is not a de Polignac number, because 71421905 - 2⁶ = 71421841 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 73070 + ... + 74040.

It is an arithmetic number, because the mean of its divisors is an integer number (5493744).

Almost surely, 2^71421905 is an apocalyptic number.

It is an amenable number.

71421905 is a deficient number, since it is larger than the sum of its proper divisors (16477999).

71421905 is a wasteful number, since it uses less digits than its factorization.

71421905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1336.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 71421905 is about 8451.1481468496. The cubic root of 71421905 is about 414.9003583298.

The spelling of 71421905 in words is "seventy-one million, four hundred twenty-one thousand, nine hundred five".