690660647 has 2 divisors, whose sum is σ = 690660648. Its totient is φ = 690660646.

The previous prime is 690660643. The next prime is 690660653. The reversal of 690660647 is 746066096.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 690660647 - 2² = 690660643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 690660598 and 690660607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (690660643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345330323 + 345330324.

It is an arithmetic number, because the mean of its divisors is an integer number (345330324).

Almost surely, 2^690660647 is an apocalyptic number.

690660647 is a deficient number, since it is larger than the sum of its proper divisors (1).

690660647 is an equidigital number, since it uses as much as digits as its factorization.

690660647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 44.

The square root of 690660647 is about 26280.4232652368. The cubic root of 690660647 is about 883.9375237372.

The spelling of 690660647 in words is "six hundred ninety million, six hundred sixty thousand, six hundred forty-seven".