40437709561 has 2 divisors, whose sum is σ = 40437709562. Its totient is φ = 40437709560.

The previous prime is 40437709537. The next prime is 40437709567. The reversal of 40437709561 is 16590773404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 36660377961 + 3777331600 = 191469^2 + 61460^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40437709561 is a prime.

It is not a weakly prime, because it can be changed into another prime (40437709567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20218854780 + 20218854781.

It is an arithmetic number, because the mean of its divisors is an integer number (20218854781).

Almost surely, 2^40437709561 is an apocalyptic number.

It is an amenable number.

40437709561 is a deficient number, since it is larger than the sum of its proper divisors (1).

40437709561 is an equidigital number, since it uses as much as digits as its factorization.

40437709561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 46.

The spelling of 40437709561 in words is "forty billion, four hundred thirty-seven million, seven hundred nine thousand, five hundred sixty-one".