71748991 has 2 divisors, whose sum is σ = 71748992. Its totient is φ = 71748990.

The previous prime is 71748977. The next prime is 71749021. The reversal of 71748991 is 19984717.

It is a weak prime.

It is an emirp because it is prime and its reverse (19984717) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71748991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71748091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35874495 + 35874496.

It is an arithmetic number, because the mean of its divisors is an integer number (35874496).

Almost surely, 2^71748991 is an apocalyptic number.

71748991 is a deficient number, since it is larger than the sum of its proper divisors (1).

71748991 is an equidigital number, since it uses as much as digits as its factorization.

71748991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 46.

The square root of 71748991 is about 8470.4776134525. The cubic root of 71748991 is about 415.5327574970.

The spelling of 71748991 in words is "seventy-one million, seven hundred forty-eight thousand, nine hundred ninety-one".