405978 has 16 divisors (see below), whose sum is σ = 824256. Its totient is φ = 133280.

The previous prime is 405967. The next prime is 405989. The reversal of 405978 is 879504.

It is an interprime number because it is at equal distance from previous prime (405967) and next prime (405989).

It is a Curzon 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, 51 + ... + 902.

It is an arithmetic number, because the mean of its divisors is an integer number (51516).

2⁴⁰⁵⁹⁷⁸ is an apocalyptic number.

405978 is an abundant number, since it is smaller than the sum of its proper divisors (418278).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

405978 is a wasteful number, since it uses less digits than its factorization.

405978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029.

The product of its (nonzero) digits is 10080, while the sum is 33.

The square root of 405978 is about 637.1640291165. The cubic root of 405978 is about 74.0458688110.

The spelling of 405978 in words is "four hundred five thousand, nine hundred seventy-eight".