40721680 has 40 divisors (see below), whose sum is σ = 95333184. Its totient is φ = 16176000.

The previous prime is 40721641. The next prime is 40721689. The reversal of 40721680 is 8612704.

It is a tau number, because it is divible by the number of its divisors (40).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10395 + ... + 13765.

Almost surely, 2^40721680 is an apocalyptic number.

40721680 is a gapful number since it is divisible by the number (40) 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 40721680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47666592).

40721680 is an abundant number, since it is smaller than the sum of its proper divisors (54611504).

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

40721680 is a wasteful number, since it uses less digits than its factorization.

40721680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3535 (or 3529 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 40721680 is about 6381.3540882794. The cubic root of 40721680 is about 344.0397015653.

The spelling of 40721680 in words is "forty million, seven hundred twenty-one thousand, six hundred eighty".