90878752681 has 2 divisors, whose sum is σ = 90878752682. Its totient is φ = 90878752680.

The previous prime is 90878752621. The next prime is 90878752703. The reversal of 90878752681 is 18625787809.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75076000000 + 15802752681 = 274000^2 + 125709^2 .

It is a cyclic number.

It is not a de Polignac number, because 90878752681 - 2⁹ = 90878752169 is a prime.

It is a super-2 number, since 2×90878752681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (90878752621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45439376340 + 45439376341.

It is an arithmetic number, because the mean of its divisors is an integer number (45439376341).

Almost surely, 2^90878752681 is an apocalyptic number.

It is an amenable number.

90878752681 is a deficient number, since it is larger than the sum of its proper divisors (1).

90878752681 is an equidigital number, since it uses as much as digits as its factorization.

90878752681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13547520, while the sum is 61.

The spelling of 90878752681 in words is "ninety billion, eight hundred seventy-eight million, seven hundred fifty-two thousand, six hundred eighty-one".