247986478 has 4 divisors (see below), whose sum is σ = 371979720. Its totient is φ = 123993238.

The previous prime is 247986467. The next prime is 247986521. The reversal of 247986478 is 874689742.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 874689742 = 2 ⋅437344871.

It is a super-2 number, since 2×247986478² = 122994586541688968, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61996618 + ... + 61996621.

It is an arithmetic number, because the mean of its divisors is an integer number (92994930).

Almost surely, 2^247986478 is an apocalyptic number.

247986478 is a deficient number, since it is larger than the sum of its proper divisors (123993242).

247986478 is a wasteful number, since it uses less digits than its factorization.

247986478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123993241.

The product of its digits is 5419008, while the sum is 55.

The square root of 247986478 is about 15747.5864182420. The cubic root of 247986478 is about 628.2647115210.

The spelling of 247986478 in words is "two hundred forty-seven million, nine hundred eighty-six thousand, four hundred seventy-eight".