40006521 has 16 divisors (see below), whose sum is σ = 59377920. Its totient is φ = 26622000.

The previous prime is 40006517. The next prime is 40006537. The reversal of 40006521 is 12560004.

It is a happy number.

It is not a de Polignac number, because 40006521 - 2² = 40006517 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40006494 and 40006503.

It is not an unprimeable number, because it can be changed into a prime (40006501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19291 + ... + 21263.

It is an arithmetic number, because the mean of its divisors is an integer number (3711120).

Almost surely, 2^40006521 is an apocalyptic number.

It is an amenable number.

40006521 is a deficient number, since it is larger than the sum of its proper divisors (19371399).

40006521 is a wasteful number, since it uses less digits than its factorization.

40006521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2733 (or 2727 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 40006521 is about 6325.0708296429. The cubic root of 40006521 is about 342.0137729141.

Adding to 40006521 its reverse (12560004), we get a palindrome (52566525).

The spelling of 40006521 in words is "forty million, six thousand, five hundred twenty-one".