29128640 has 56 divisors (see below), whose sum is σ = 69841872. Its totient is φ = 11571200.

The previous prime is 29128621. The next prime is 29128651. The reversal of 29128640 is 4682192.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 29128597 and 29128606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72440 + ... + 72840.

Almost surely, 2^29128640 is an apocalyptic number.

29128640 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 29128640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34920936).

29128640 is an abundant number, since it is smaller than the sum of its proper divisors (40713232).

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

29128640 is a wasteful number, since it uses less digits than its factorization.

29128640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645 (or 635 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 29128640 is about 5397.0955151822. The cubic root of 29128640 is about 307.6852916349.

The spelling of 29128640 in words is "twenty-nine million, one hundred twenty-eight thousand, six hundred forty".