71997137 has 4 divisors (see below), whose sum is σ = 75786480. Its totient is φ = 68207796.

The previous prime is 71997131. The next prime is 71997139. The reversal of 71997137 is 73179917.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 71997137 - 2⁶ = 71997073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71997131) 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, 1894643 + ... + 1894680.

It is an arithmetic number, because the mean of its divisors is an integer number (18946620).

Almost surely, 2^71997137 is an apocalyptic number.

It is an amenable number.

71997137 is a deficient number, since it is larger than the sum of its proper divisors (3789343).

71997137 is a wasteful number, since it uses less digits than its factorization.

71997137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3789342.

The product of its digits is 83349, while the sum is 44.

The square root of 71997137 is about 8485.1126686686. The cubic root of 71997137 is about 416.0112503892.

The spelling of 71997137 in words is "seventy-one million, nine hundred ninety-seven thousand, one hundred thirty-seven".