66891087478 has 8 divisors (see below), whose sum is σ = 100937449872. Its totient is φ = 33245270856.

The previous prime is 66891087463. The next prime is 66891087521. The reversal of 66891087478 is 87478019866.

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

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, 100136025 + ... + 100136692.

It is an arithmetic number, because the mean of its divisors is an integer number (12617181234).

Almost surely, 2^66891087478 is an apocalyptic number.

66891087478 is a deficient number, since it is larger than the sum of its proper divisors (34046362394).

66891087478 is a wasteful number, since it uses less digits than its factorization.

66891087478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200272886.

The product of its (nonzero) digits is 32514048, while the sum is 64.

The spelling of 66891087478 in words is "sixty-six billion, eight hundred ninety-one million, eighty-seven thousand, four hundred seventy-eight".