646290478 has 8 divisors (see below), whose sum is σ = 1011585168. Its totient is φ = 309095424.

The previous prime is 646290461. The next prime is 646290481. The reversal of 646290478 is 874092646.

It is a happy number.

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

It is a Harshad number since it is a multiple of its sum of digits (46), and also a Moran number because the ratio is a prime number: 14049793 = 646290478 / (6 + 4 + 6 + 2 + 9 + 0 + 4 + 7 + 8).

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, 7024851 + ... + 7024942.

It is an arithmetic number, because the mean of its divisors is an integer number (126448146).

Almost surely, 2^646290478 is an apocalyptic number.

646290478 is a deficient number, since it is larger than the sum of its proper divisors (365294690).

646290478 is a wasteful number, since it uses less digits than its factorization.

646290478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14049818.

The product of its (nonzero) digits is 580608, while the sum is 46.

The square root of 646290478 is about 25422.2437640740. The cubic root of 646290478 is about 864.5880975164.

The spelling of 646290478 in words is "six hundred forty-six million, two hundred ninety thousand, four hundred seventy-eight".