71625661 has 2 divisors, whose sum is σ = 71625662. Its totient is φ = 71625660.

The previous prime is 71625577. The next prime is 71625667. The reversal of 71625661 is 16652617.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69405561 + 2220100 = 8331^2 + 1490^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71625661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71625667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35812830 + 35812831.

It is an arithmetic number, because the mean of its divisors is an integer number (35812831).

Almost surely, 2^71625661 is an apocalyptic number.

It is an amenable number.

71625661 is a deficient number, since it is larger than the sum of its proper divisors (1).

71625661 is an equidigital number, since it uses as much as digits as its factorization.

71625661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15120, while the sum is 34.

The square root of 71625661 is about 8463.1944914435. The cubic root of 71625661 is about 415.2945332577.

The spelling of 71625661 in words is "seventy-one million, six hundred twenty-five thousand, six hundred sixty-one".