40001999977 has 2 divisors, whose sum is σ = 40001999978. Its totient is φ = 40001999976.

The previous prime is 40001999971. The next prime is 40001999987. The reversal of 40001999977 is 77999910004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22759946496 + 17242053481 = 150864^2 + 131309^2 .

It is a cyclic number.

It is not a de Polignac number, because 40001999977 - 2¹¹ = 40001997929 is a prime.

It is not a weakly prime, because it can be changed into another prime (40001999971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20000999988 + 20000999989.

It is an arithmetic number, because the mean of its divisors is an integer number (20000999989).

Almost surely, 2^40001999977 is an apocalyptic number.

It is an amenable number.

40001999977 is a deficient number, since it is larger than the sum of its proper divisors (1).

40001999977 is an equidigital number, since it uses as much as digits as its factorization.

40001999977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1285956, while the sum is 55.

The spelling of 40001999977 in words is "forty billion, one million, nine hundred ninety-nine thousand, nine hundred seventy-seven".