39778645 has 8 divisors (see below), whose sum is σ = 47840256. Its totient is φ = 31752336.

The previous prime is 39778643. The next prime is 39778667. The reversal of 39778645 is 54687793.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 39778645 - 2¹ = 39778643 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39778643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6277 + ... + 10906.

It is an arithmetic number, because the mean of its divisors is an integer number (5980032).

Almost surely, 2^39778645 is an apocalyptic number.

It is an amenable number.

39778645 is a deficient number, since it is larger than the sum of its proper divisors (8061611).

39778645 is a wasteful number, since it uses less digits than its factorization.

39778645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17651.

The product of its digits is 1270080, while the sum is 49.

The square root of 39778645 is about 6307.0313936114. The cubic root of 39778645 is about 341.3631691814.

The spelling of 39778645 in words is "thirty-nine million, seven hundred seventy-eight thousand, six hundred forty-five".