71997655 has 16 divisors (see below), whose sum is σ = 91090944. Its totient is φ = 54548640.

The previous prime is 71997649. The next prime is 71997683. The reversal of 71997655 is 55679917.

It is not a de Polignac number, because 71997655 - 2³ = 71997647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71997599 and 71997608.

It is a congruent 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, 2344 + ... + 12226.

It is an arithmetic number, because the mean of its divisors is an integer number (5693184).

Almost surely, 2^71997655 is an apocalyptic number.

71997655 is a deficient number, since it is larger than the sum of its proper divisors (19093289).

71997655 is a wasteful number, since it uses less digits than its factorization.

71997655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9966.

The product of its digits is 595350, while the sum is 49.

The square root of 71997655 is about 8485.1431926633. The cubic root of 71997655 is about 416.0122480830.

The spelling of 71997655 in words is "seventy-one million, nine hundred ninety-seven thousand, six hundred fifty-five".