40102217891 has 2 divisors, whose sum is σ = 40102217892. Its totient is φ = 40102217890.

The previous prime is 40102217879. The next prime is 40102217971. The reversal of 40102217891 is 19871220104.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 40102217891 - 2²² = 40098023587 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (40102217791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20051108945 + 20051108946.

It is an arithmetic number, because the mean of its divisors is an integer number (20051108946).

Almost surely, 2^40102217891 is an apocalyptic number.

40102217891 is a deficient number, since it is larger than the sum of its proper divisors (1).

40102217891 is an equidigital number, since it uses as much as digits as its factorization.

40102217891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 35.

Adding to 40102217891 its reverse (19871220104), we get a palindrome (59973437995).

The spelling of 40102217891 in words is "forty billion, one hundred two million, two hundred seventeen thousand, eight hundred ninety-one".