70778881 has 4 divisors (see below), whose sum is σ = 71479764. Its totient is φ = 70078000.

The previous prime is 70778861. The next prime is 70778893. The reversal of 70778881 is 18887707.

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 67092481 + 3686400 = 8191^2 + 1920^2 .

It is a cyclic number.

It is not a de Polignac number, because 70778881 - 2¹¹ = 70776833 is a prime.

It is a super-2 number, since 2×70778881² = 10019299991224322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (70778801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 350290 + ... + 350491.

It is an arithmetic number, because the mean of its divisors is an integer number (17869941).

It is a Proth number, since it is equal to 135 ⋅ 2¹⁹ + 1 and 135 < 2¹⁹.

Almost surely, 2^70778881 is an apocalyptic number.

It is an amenable number.

70778881 is a deficient number, since it is larger than the sum of its proper divisors (700883).

70778881 is a wasteful number, since it uses less digits than its factorization.

70778881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700882.

The product of its (nonzero) digits is 175616, while the sum is 46.

The square root of 70778881 is about 8413.0185427111. The cubic root of 70778881 is about 413.6514624342.

The spelling of 70778881 in words is "seventy million, seven hundred seventy-eight thousand, eight hundred eighty-one".