405091890 has 96 divisors (see below), whose sum is σ = 1233138816. Its totient is φ = 90328320.

The previous prime is 405091889. The next prime is 405091901. The reversal of 405091890 is 98190504.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17989 + ... + 33671.

It is an arithmetic number, because the mean of its divisors is an integer number (12845196).

Almost surely, 2^405091890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405091890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (616569408).

405091890 is an abundant number, since it is smaller than the sum of its proper divisors (828046926).

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

405091890 is a wasteful number, since it uses less digits than its factorization.

405091890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15744 (or 15741 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 405091890 is about 20126.8946934195. The cubic root of 405091890 is about 739.9195736795.

The spelling of 405091890 in words is "four hundred five million, ninety-one thousand, eight hundred ninety".