400778424 has 24 divisors (see below), whose sum is σ = 1085441760. Its totient is φ = 133592784.

The previous prime is 400778423. The next prime is 400778431. The reversal of 400778424 is 424877004.

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400778423) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2783112 + ... + 2783255.

It is an arithmetic number, because the mean of its divisors is an integer number (45226740).

Almost surely, 2^400778424 is an apocalyptic number.

It is an amenable number.

400778424 is an abundant number, since it is smaller than the sum of its proper divisors (684663336).

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

400778424 is a wasteful number, since it uses less digits than its factorization.

400778424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5566379 (or 5566372 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 36.

The square root of 400778424 is about 20019.4511413275. The cubic root of 400778424 is about 737.2839464414.

The spelling of 400778424 in words is "four hundred million, seven hundred seventy-eight thousand, four hundred twenty-four".