402978385 has 8 divisors (see below), whose sum is σ = 488362536. Its totient is φ = 319190400.

The previous prime is 402978349. The next prime is 402978419. The reversal of 402978385 is 583879204.

It can be written as a sum of positive squares in 4 ways, for example, as 261177921 + 141800464 = 16161^2 + 11908^2 .

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

It is not a de Polignac number, because 402978385 - 2⁹ = 402977873 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 398484 + ... + 399493.

It is an arithmetic number, because the mean of its divisors is an integer number (61045317).

Almost surely, 2^402978385 is an apocalyptic number.

It is an amenable number.

402978385 is a deficient number, since it is larger than the sum of its proper divisors (85384151).

402978385 is a wasteful number, since it uses less digits than its factorization.

402978385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 798083.

The product of its (nonzero) digits is 483840, while the sum is 46.

The square root of 402978385 is about 20074.3215327443. The cubic root of 402978385 is about 738.6305235173.

The spelling of 402978385 in words is "four hundred two million, nine hundred seventy-eight thousand, three hundred eighty-five".