787978969 has 2 divisors, whose sum is σ = 787978970. Its totient is φ = 787978968.

The previous prime is 787978967. The next prime is 787979021. The reversal of 787978969 is 969879787.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 509088969 + 278890000 = 22563^2 + 16700^2 .

It is an emirp because it is prime and its reverse (969879787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 787978969 - 2¹ = 787978967 is a prime.

It is a super-2 number, since 2×787978969² = 1241821711172605922, which contains 22 as substring.

Together with 787978967, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 787978898 and 787978907.

It is not a weakly prime, because it can be changed into another prime (787978967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 393989484 + 393989485.

It is an arithmetic number, because the mean of its divisors is an integer number (393989485).

Almost surely, 2^787978969 is an apocalyptic number.

It is an amenable number.

787978969 is a deficient number, since it is larger than the sum of its proper divisors (1).

787978969 is an equidigital number, since it uses as much as digits as its factorization.

787978969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96018048, while the sum is 70.

The square root of 787978969 is about 28070.9630935599. The cubic root of 787978969 is about 923.6445573671.

The spelling of 787978969 in words is "seven hundred eighty-seven million, nine hundred seventy-eight thousand, nine hundred sixty-nine".