78250905 has 12 divisors (see below), whose sum is σ = 135634980. Its totient is φ = 41733792.

The previous prime is 78250901. The next prime is 78250937. The reversal of 78250905 is 50905287.

It can be written as a sum of positive squares in 2 ways, for example, as 44796249 + 33454656 = 6693^2 + 5784^2 .

It is not a de Polignac number, because 78250905 - 2² = 78250901 is a prime.

It is a super-2 number, since 2×78250905² = 12246408266638050, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78250905.

It is not an unprimeable number, because it can be changed into a prime (78250901) 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 in 11 ways as a sum of consecutive naturals, for example, 869410 + ... + 869499.

It is an arithmetic number, because the mean of its divisors is an integer number (11302915).

Almost surely, 2^78250905 is an apocalyptic number.

It is an amenable number.

78250905 is a deficient number, since it is larger than the sum of its proper divisors (57384075).

78250905 is a wasteful number, since it uses less digits than its factorization.

78250905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1738920 (or 1738917 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 36.

The square root of 78250905 is about 8845.9541599536. The cubic root of 78250905 is about 427.7235109038.

The spelling of 78250905 in words is "seventy-eight million, two hundred fifty thousand, nine hundred five".