661095947 has 2 divisors, whose sum is σ = 661095948. Its totient is φ = 661095946.

The previous prime is 661095943. The next prime is 661095973. The reversal of 661095947 is 749590166.

661095947 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 661095947 - 2² = 661095943 is a prime.

It is a super-2 number, since 2×661095947² = 874095702279653618, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (661095943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330547973 + 330547974.

It is an arithmetic number, because the mean of its divisors is an integer number (330547974).

Almost surely, 2^661095947 is an apocalyptic number.

661095947 is a deficient number, since it is larger than the sum of its proper divisors (1).

661095947 is an equidigital number, since it uses as much as digits as its factorization.

661095947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 408240, while the sum is 47.

The square root of 661095947 is about 25711.7861495463. The cubic root of 661095947 is about 871.1404197220.

The spelling of 661095947 in words is "six hundred sixty-one million, ninety-five thousand, nine hundred forty-seven".