40021145 has 8 divisors (see below), whose sum is σ = 50850504. Its totient is φ = 30133504.

The previous prime is 40021123. The next prime is 40021147. The reversal of 40021145 is 54112004.

It can be written as a sum of positive squares in 4 ways, for example, as 7268416 + 32752729 = 2696^2 + 5723^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 40021145 - 2¹⁶ = 39955609 is a prime.

It is a super-2 number, since 2×40021145² = 3203384094222050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40021147) 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, 235334 + ... + 235503.

It is an arithmetic number, because the mean of its divisors is an integer number (6356313).

Almost surely, 2^40021145 is an apocalyptic number.

It is an amenable number.

40021145 is a deficient number, since it is larger than the sum of its proper divisors (10829359).

40021145 is a wasteful number, since it uses less digits than its factorization.

40021145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 470859.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 40021145 is about 6326.2267585030. The cubic root of 40021145 is about 342.0554411220.

Adding to 40021145 its reverse (54112004), we get a palindrome (94133149).

The spelling of 40021145 in words is "forty million, twenty-one thousand, one hundred forty-five".