40213661 has 8 divisors (see below), whose sum is σ = 41524224. Its totient is φ = 38918880.

The previous prime is 40213651. The next prime is 40213681. The reversal of 40213661 is 16631204.

It is a happy number.

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 40213661 - 2⁶ = 40213597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40213651) 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, 1346 + ... + 9068.

It is an arithmetic number, because the mean of its divisors is an integer number (5190528).

Almost surely, 2^40213661 is an apocalyptic number.

40213661 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

40213661 is a deficient number, since it is larger than the sum of its proper divisors (1310563).

40213661 is a wasteful number, since it uses less digits than its factorization.

40213661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7891.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 40213661 is about 6341.4242091190. The cubic root of 40213661 is about 342.6030336293.

Adding to 40213661 its reverse (16631204), we get a palindrome (56844865).

The spelling of 40213661 in words is "forty million, two hundred thirteen thousand, six hundred sixty-one".