670726778 has 8 divisors (see below), whose sum is σ = 1012842900. Its totient is φ = 333112480.

The previous prime is 670726747. The next prime is 670726811. The reversal of 670726778 is 877627076.

It can be written as a sum of positive squares in 2 ways, for example, as 623351089 + 47375689 = 24967^2 + 6883^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×670726778² = 899748821452522568, which contains 22 as substring.

It is a Curzon 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, 1125083 + ... + 1125678.

Almost surely, 2^670726778 is an apocalyptic number.

670726778 is a deficient number, since it is larger than the sum of its proper divisors (342116122).

670726778 is a wasteful number, since it uses less digits than its factorization.

670726778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2250912.

The product of its (nonzero) digits is 1382976, while the sum is 50.

The square root of 670726778 is about 25898.3933478508. The cubic root of 670726778 is about 875.3502937054.

The spelling of 670726778 in words is "six hundred seventy million, seven hundred twenty-six thousand, seven hundred seventy-eight".