29805840 has 80 divisors (see below), whose sum is σ = 102672000. Its totient is φ = 7947648.

The previous prime is 29805829. The next prime is 29805847. The reversal of 29805840 is 4850892.

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

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 29805795 and 29805804.

It is not an unprimeable number, because it can be changed into a prime (29805847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4740 + ... + 9059.

It is an arithmetic number, because the mean of its divisors is an integer number (1283400).

Almost surely, 2^29805840 is an apocalyptic number.

29805840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

29805840 is an abundant number, since it is smaller than the sum of its proper divisors (72866160).

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

29805840 is a wasteful number, since it uses less digits than its factorization.

29805840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13821 (or 13809 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 29805840 is about 5459.4725019914. The cubic root of 29805840 is about 310.0514656142.

The spelling of 29805840 in words is "twenty-nine million, eight hundred five thousand, eight hundred forty".