71778533 has 2 divisors, whose sum is σ = 71778534. Its totient is φ = 71778532.

The previous prime is 71778529. The next prime is 71778569. The reversal of 71778533 is 33587717.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50452609 + 21325924 = 7103^2 + 4618^2 .

It is a cyclic number.

It is not a de Polignac number, because 71778533 - 2² = 71778529 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71778503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35889266 + 35889267.

It is an arithmetic number, because the mean of its divisors is an integer number (35889267).

Almost surely, 2^71778533 is an apocalyptic number.

It is an amenable number.

71778533 is a deficient number, since it is larger than the sum of its proper divisors (1).

71778533 is an equidigital number, since it uses as much as digits as its factorization.

71778533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 123480, while the sum is 41.

The square root of 71778533 is about 8472.2212553734. The cubic root of 71778533 is about 415.5897802933.

The spelling of 71778533 in words is "seventy-one million, seven hundred seventy-eight thousand, five hundred thirty-three".