797779987 has 2 divisors, whose sum is σ = 797779988. Its totient is φ = 797779986.

The previous prime is 797779973. The next prime is 797779991. The reversal of 797779987 is 789977797.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-797779987 is a prime.

It is not a weakly prime, because it can be changed into another prime (797777987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 398889993 + 398889994.

It is an arithmetic number, because the mean of its divisors is an integer number (398889994).

Almost surely, 2^797779987 is an apocalyptic number.

797779987 is a deficient number, since it is larger than the sum of its proper divisors (1).

797779987 is an equidigital number, since it uses as much as digits as its factorization.

797779987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 98018424, while the sum is 70.

The square root of 797779987 is about 28244.9993273146. Note that the first 3 decimals coincide. The cubic root of 797779987 is about 927.4582722319.

The spelling of 797779987 in words is "seven hundred ninety-seven million, seven hundred seventy-nine thousand, nine hundred eighty-seven".