405861855 has 24 divisors (see below), whose sum is σ = 755401392. Its totient is φ = 185536512.

The previous prime is 405861851. The next prime is 405861857. The reversal of 405861855 is 558168504.

It is not a de Polignac number, because 405861855 - 2² = 405861851 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405861851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 275362 + ... + 276831.

It is an arithmetic number, because the mean of its divisors is an integer number (31475058).

Almost surely, 2^405861855 is an apocalyptic number.

405861855 is a deficient number, since it is larger than the sum of its proper divisors (349539537).

405861855 is a wasteful number, since it uses less digits than its factorization.

405861855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 552215 (or 552208 counting only the distinct ones).

The product of its (nonzero) digits is 192000, while the sum is 42.

The square root of 405861855 is about 20146.0133773409. The cubic root of 405861855 is about 740.3880695240.

The spelling of 405861855 in words is "four hundred five million, eight hundred sixty-one thousand, eight hundred fifty-five".