40721913 has 8 divisors (see below), whose sum is σ = 60328800. Its totient is φ = 27147924.

The previous prime is 40721873. The next prime is 40721917. The reversal of 40721913 is 31912704.

It is not a de Polignac number, because 40721913 - 2¹⁷ = 40590841 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1508219 = 40721913 / (4 + 0 + 7 + 2 + 1 + 9 + 1 + 3).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (40721917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 754083 + ... + 754136.

It is an arithmetic number, because the mean of its divisors is an integer number (7541100).

Almost surely, 2^40721913 is an apocalyptic number.

It is an amenable number.

40721913 is a deficient number, since it is larger than the sum of its proper divisors (19606887).

40721913 is a wasteful number, since it uses less digits than its factorization.

40721913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1508228 (or 1508222 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 40721913 is about 6381.3723445666. The cubic root of 40721913 is about 344.0403577358.

The spelling of 40721913 in words is "forty million, seven hundred twenty-one thousand, nine hundred thirteen".