405685764 has 144 divisors (see below), whose sum is σ = 1162377216. Its totient is φ = 118238400.

The previous prime is 405685757. The next prime is 405685771. The reversal of 405685764 is 467586504.

It is an interprime number because it is at equal distance from previous prime (405685757) and next prime (405685771).

It is a super-2 number, since 2×405685764² = 329161878224527392, which contains 22 as substring.

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, 1321299 + ... + 1321605.

It is an arithmetic number, because the mean of its divisors is an integer number (8072064).

Almost surely, 2^405685764 is an apocalyptic number.

405685764 is a gapful number since it is divisible by the number (44) 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 405685764, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (581188608).

405685764 is an abundant number, since it is smaller than the sum of its proper divisors (756691452).

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

405685764 is a wasteful number, since it uses less digits than its factorization.

405685764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 446 (or 441 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The square root of 405685764 is about 20141.6425348083. The cubic root of 405685764 is about 740.2809768160.

The spelling of 405685764 in words is "four hundred five million, six hundred eighty-five thousand, seven hundred sixty-four".