40747561 has 4 divisors (see below), whose sum is σ = 40768000. Its totient is φ = 40727124.

The previous prime is 40747519. The next prime is 40747601. The reversal of 40747561 is 16574704.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40747561 - 2¹⁷ = 40616489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40745561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6861 + ... + 11338.

It is an arithmetic number, because the mean of its divisors is an integer number (10192000).

Almost surely, 2^40747561 is an apocalyptic number.

It is an amenable number.

40747561 is a deficient number, since it is larger than the sum of its proper divisors (20439).

40747561 is a wasteful number, since it uses less digits than its factorization.

40747561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20438.

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 40747561 is about 6383.3816273195. The cubic root of 40747561 is about 344.1125718875.

The spelling of 40747561 in words is "forty million, seven hundred forty-seven thousand, five hundred sixty-one".