661003769 has 2 divisors, whose sum is σ = 661003770. Its totient is φ = 661003768.

The previous prime is 661003663. The next prime is 661003771. The reversal of 661003769 is 967300166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 442555369 + 218448400 = 21037^2 + 14780^2 .

It is a cyclic number.

It is not a de Polignac number, because 661003769 - 2⁸ = 661003513 is a prime.

It is a super-2 number, since 2×661003769² = 873851965264410722, which contains 22 as substring.

Together with 661003771, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (661003789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330501884 + 330501885.

It is an arithmetic number, because the mean of its divisors is an integer number (330501885).

Almost surely, 2^661003769 is an apocalyptic number.

It is an amenable number.

661003769 is a deficient number, since it is larger than the sum of its proper divisors (1).

661003769 is an equidigital number, since it uses as much as digits as its factorization.

661003769 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 38.

The square root of 661003769 is about 25709.9935628152. The cubic root of 661003769 is about 871.0999295257.

The spelling of 661003769 in words is "six hundred sixty-one million, three thousand, seven hundred sixty-nine".