40721688 has 96 divisors (see below), whose sum is σ = 129043200. Its totient is φ = 11358144.

The previous prime is 40721641. The next prime is 40721689. The reversal of 40721688 is 88612704.

40721688 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40721689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20733 + ... + 22611.

It is an arithmetic number, because the mean of its divisors is an integer number (1344200).

Almost surely, 2^40721688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40721688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64521600).

40721688 is an abundant number, since it is smaller than the sum of its proper divisors (88321512).

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

40721688 is a wasteful number, since it uses less digits than its factorization.

40721688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941 (or 1934 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 40721688 is about 6381.3547151056. The cubic root of 40721688 is about 344.0397240948.

The spelling of 40721688 in words is "forty million, seven hundred twenty-one thousand, six hundred eighty-eight".