661395043 has 2 divisors, whose sum is σ = 661395044. Its totient is φ = 661395042.

The previous prime is 661395041. The next prime is 661395101. The reversal of 661395043 is 340593166.

661395043 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661395043 - 2¹ = 661395041 is a prime.

Together with 661395041, it forms a pair of twin primes.

It is equal to p_34354945 and since 661395043 and 34354945 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 661394993 and 661395011.

It is not a weakly prime, because it can be changed into another prime (661395041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330697521 + 330697522.

It is an arithmetic number, because the mean of its divisors is an integer number (330697522).

Almost surely, 2^661395043 is an apocalyptic number.

661395043 is a deficient number, since it is larger than the sum of its proper divisors (1).

661395043 is an equidigital number, since it uses as much as digits as its factorization.

661395043 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 37.

The square root of 661395043 is about 25717.6018127663. The cubic root of 661395043 is about 871.2717750027.

The spelling of 661395043 in words is "six hundred sixty-one million, three hundred ninety-five thousand, forty-three".