405155440 has 80 divisors (see below), whose sum is σ = 975312576. Its totient is φ = 156416000.

The previous prime is 405155437. The next prime is 405155467. The reversal of 405155440 is 44551504.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 405155399 and 405155408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 330669 + ... + 331891.

Almost surely, 2^405155440 is an apocalyptic number.

405155440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405155440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (487656288).

405155440 is an abundant number, since it is smaller than the sum of its proper divisors (570157136).

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

405155440 is a wasteful number, since it uses less digits than its factorization.

405155440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378 (or 1372 counting only the distinct ones).

The product of its (nonzero) digits is 8000, while the sum is 28.

The square root of 405155440 is about 20128.4733648630. The cubic root of 405155440 is about 739.9582640206.

The spelling of 405155440 in words is "four hundred five million, one hundred fifty-five thousand, four hundred forty".