405106636506 has 128 divisors (see below), whose sum is σ = 993805424640. Its totient is φ = 108328492800.

The previous prime is 405106636489. The next prime is 405106636507. The reversal of 405106636506 is 605636601504.

It is a super-2 number, since 2×405106636506² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (405106636507) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 42995676 + ... + 43005096.

It is an arithmetic number, because the mean of its divisors is an integer number (7764104880).

Almost surely, 2^405106636506 is an apocalyptic number.

405106636506 is a gapful number since it is divisible by the number (46) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 405106636506, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (496902712320).

405106636506 is an abundant number, since it is smaller than the sum of its proper divisors (588698788134).

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

405106636506 is a wasteful number, since it uses less digits than its factorization.

405106636506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11652.

The product of its (nonzero) digits is 388800, while the sum is 42.

The spelling of 405106636506 in words is "four hundred five billion, one hundred six million, six hundred thirty-six thousand, five hundred six".