39987684197 has 2 divisors, whose sum is σ = 39987684198. Its totient is φ = 39987684196.

The previous prime is 39987684179. The next prime is 39987684313. The reversal of 39987684197 is 79148678993.

Together with previous prime (39987684179) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35942851396 + 4044832801 = 189586^2 + 63599^2 .

It is a cyclic number.

It is not a de Polignac number, because 39987684197 - 2¹⁰ = 39987683173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 39987684197.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39987684167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19993842098 + 19993842099.

It is an arithmetic number, because the mean of its divisors is an integer number (19993842099).

Almost surely, 2^39987684197 is an apocalyptic number.

It is an amenable number.

39987684197 is a deficient number, since it is larger than the sum of its proper divisors (1).

39987684197 is an equidigital number, since it uses as much as digits as its factorization.

39987684197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 164602368, while the sum is 71.

The spelling of 39987684197 in words is "thirty-nine billion, nine hundred eighty-seven million, six hundred eighty-four thousand, one hundred ninety-seven".