29121680 has 240 divisors, whose sum is σ = 91601280. Its totient is φ = 8515584.

The previous prime is 29121667. The next prime is 29121683. The reversal of 29121680 is 8612192.

It is not an unprimeable number, because it can be changed into a prime (29121683) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1266149 + ... + 1266171.

It is an arithmetic number, because the mean of its divisors is an integer number (381672).

Almost surely, 2^29121680 is an apocalyptic number.

29121680 is a gapful number since it is divisible by the number (20) 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 29121680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45800640).

29121680 is an abundant number, since it is smaller than the sum of its proper divisors (62479600).

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

29121680 is a wasteful number, since it uses less digits than its factorization.

29121680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 29121680 is about 5396.4506854043. The cubic root of 29121680 is about 307.6607835652.

The spelling of 29121680 in words is "twenty-nine million, one hundred twenty-one thousand, six hundred eighty".