90778645 has 4 divisors (see below), whose sum is σ = 108934380. Its totient is φ = 72622912.

The previous prime is 90778621. The next prime is 90778651. The reversal of 90778645 is 54687709.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 51753636 + 39025009 = 7194^2 + 6247^2 .

It is a cyclic number.

It is not a de Polignac number, because 90778645 - 2⁹ = 90778133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 90778595 and 90778604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9077860 + ... + 9077869.

It is an arithmetic number, because the mean of its divisors is an integer number (27233595).

Almost surely, 2^90778645 is an apocalyptic number.

It is an amenable number.

90778645 is a deficient number, since it is larger than the sum of its proper divisors (18155735).

90778645 is a wasteful number, since it uses less digits than its factorization.

90778645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18155734.

The product of its (nonzero) digits is 423360, while the sum is 46.

The square root of 90778645 is about 9527.7827955931. The cubic root of 90778645 is about 449.4291444500.

The spelling of 90778645 in words is "ninety million, seven hundred seventy-eight thousand, six hundred forty-five".