85520381 has 2 divisors, whose sum is σ = 85520382. Its totient is φ = 85520380.

The previous prime is 85520377. The next prime is 85520389. The reversal of 85520381 is 18302558.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62805625 + 22714756 = 7925^2 + 4766^2 .

It is a cyclic number.

It is not a de Polignac number, because 85520381 - 2² = 85520377 is a prime.

It is a super-2 number, since 2×85520381² = 14627471132770322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85520389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42760190 + 42760191.

It is an arithmetic number, because the mean of its divisors is an integer number (42760191).

Almost surely, 2^85520381 is an apocalyptic number.

It is an amenable number.

85520381 is a deficient number, since it is larger than the sum of its proper divisors (1).

85520381 is an equidigital number, since it uses as much as digits as its factorization.

85520381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 85520381 is about 9247.7230170459. The cubic root of 85520381 is about 440.5784077019.

The spelling of 85520381 in words is "eighty-five million, five hundred twenty thousand, three hundred eighty-one".