40206561 has 8 divisors (see below), whose sum is σ = 53638944. Its totient is φ = 26789280.

The previous prime is 40206539. The next prime is 40206571. The reversal of 40206561 is 16560204.

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

It is not a de Polignac number, because 40206561 - 2¹⁰ = 40205537 is a prime.

It is not an unprimeable number, because it can be changed into a prime (40206511) 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, 6226 + ... + 10916.

It is an arithmetic number, because the mean of its divisors is an integer number (6704868).

Almost surely, 2^40206561 is an apocalyptic number.

It is an amenable number.

40206561 is a deficient number, since it is larger than the sum of its proper divisors (13432383).

40206561 is a wasteful number, since it uses less digits than its factorization.

40206561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7551.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 40206561 is about 6340.8643732539. The cubic root of 40206561 is about 342.5828694641.

Adding to 40206561 its reverse (16560204), we get a palindrome (56766765).

The spelling of 40206561 in words is "forty million, two hundred six thousand, five hundred sixty-one".