40721791 has 8 divisors (see below), whose sum is σ = 44495568. Its totient is φ = 36960000.

The previous prime is 40721789. The next prime is 40721797. The reversal of 40721791 is 19712704.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 40721791 - 2¹ = 40721789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40721797) 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, 5071 + ... + 10351.

It is an arithmetic number, because the mean of its divisors is an integer number (5561946).

Almost surely, 2^40721791 is an apocalyptic number.

40721791 is a deficient number, since it is larger than the sum of its proper divisors (3773777).

40721791 is a wasteful number, since it uses less digits than its factorization.

40721791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5993.

The product of its (nonzero) digits is 3528, while the sum is 31.

The square root of 40721791 is about 6381.3627854871. The cubic root of 40721791 is about 344.0400141618.

The spelling of 40721791 in words is "forty million, seven hundred twenty-one thousand, seven hundred ninety-one".