40729321 has 4 divisors (see below), whose sum is σ = 40742100. Its totient is φ = 40716544.

The previous prime is 40729313. The next prime is 40729327. The reversal of 40729321 is 12392704.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 21902400 + 18826921 = 4680^2 + 4339^2 .

It is a cyclic number.

It is not a de Polignac number, because 40729321 - 2³ = 40729313 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 40729321.

It is not an unprimeable number, because it can be changed into a prime (40729327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2745 + ... + 9433.

It is an arithmetic number, because the mean of its divisors is an integer number (10185525).

Almost surely, 2^40729321 is an apocalyptic number.

It is an amenable number.

40729321 is a deficient number, since it is larger than the sum of its proper divisors (12779).

40729321 is an equidigital number, since it uses as much as digits as its factorization.

40729321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12778.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 40729321 is about 6381.9527575813. The cubic root of 40729321 is about 344.0612187109.

The spelling of 40729321 in words is "forty million, seven hundred twenty-nine thousand, three hundred twenty-one".