661742023 has 2 divisors, whose sum is σ = 661742024. Its totient is φ = 661742022.

The previous prime is 661741991. The next prime is 661742033. The reversal of 661742023 is 320247166.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 661742023 - 2⁵ = 661741991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661742033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330871011 + 330871012.

It is an arithmetic number, because the mean of its divisors is an integer number (330871012).

Almost surely, 2^661742023 is an apocalyptic number.

661742023 is a deficient number, since it is larger than the sum of its proper divisors (1).

661742023 is an equidigital number, since it uses as much as digits as its factorization.

661742023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 661742023 is about 25724.3468916122. The cubic root of 661742023 is about 871.4241100973.

Adding to 661742023 its reverse (320247166), we get a palindrome (981989189).

The spelling of 661742023 in words is "six hundred sixty-one million, seven hundred forty-two thousand, twenty-three".