40739561 has 4 divisors (see below), whose sum is σ = 40809552. Its totient is φ = 40669572.

The previous prime is 40739557. The next prime is 40739579. The reversal of 40739561 is 16593704.

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 40739561 - 2² = 40739557 is a prime.

It is a super-4 number, since 4×40739561⁴ (a number of 32 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40739261) 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, 34115 + ... + 35288.

It is an arithmetic number, because the mean of its divisors is an integer number (10202388).

Almost surely, 2^40739561 is an apocalyptic number.

It is an amenable number.

40739561 is a deficient number, since it is larger than the sum of its proper divisors (69991).

40739561 is an equidigital number, since it uses as much as digits as its factorization.

40739561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69990.

The product of its (nonzero) digits is 22680, while the sum is 35.

The square root of 40739561 is about 6382.7549694470. The cubic root of 40739561 is about 344.0900504515.

The spelling of 40739561 in words is "forty million, seven hundred thirty-nine thousand, five hundred sixty-one".