20195639377 has 2 divisors, whose sum is σ = 20195639378. Its totient is φ = 20195639376.

The previous prime is 20195639341. The next prime is 20195639423. The reversal of 20195639377 is 77393659102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18332076816 + 1863562561 = 135396^2 + 43169^2 .

It is a cyclic number.

It is not a de Polignac number, because 20195639377 - 2⁷ = 20195639249 is a prime.

It is not a weakly prime, because it can be changed into another prime (20195609377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10097819688 + 10097819689.

It is an arithmetic number, because the mean of its divisors is an integer number (10097819689).

Almost surely, 2^20195639377 is an apocalyptic number.

It is an amenable number.

20195639377 is a deficient number, since it is larger than the sum of its proper divisors (1).

20195639377 is an equidigital number, since it uses as much as digits as its factorization.

20195639377 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2143260, while the sum is 52.

The spelling of 20195639377 in words is "twenty billion, one hundred ninety-five million, six hundred thirty-nine thousand, three hundred seventy-seven".