661969433 has 2 divisors, whose sum is σ = 661969434. Its totient is φ = 661969432.

The previous prime is 661969379. The next prime is 661969459. The reversal of 661969433 is 334969166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 616379929 + 45589504 = 24827^2 + 6752^2 .

It is a cyclic number.

It is not a de Polignac number, because 661969433 - 2⁶ = 661969369 is a prime.

It is not a weakly prime, because it can be changed into another prime (661969493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330984716 + 330984717.

It is an arithmetic number, because the mean of its divisors is an integer number (330984717).

Almost surely, 2^661969433 is an apocalyptic number.

It is an amenable number.

661969433 is a deficient number, since it is larger than the sum of its proper divisors (1).

661969433 is an equidigital number, since it uses as much as digits as its factorization.

661969433 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 47.

The square root of 661969433 is about 25728.7666435840. The cubic root of 661969433 is about 871.5239213297.

The spelling of 661969433 in words is "six hundred sixty-one million, nine hundred sixty-nine thousand, four hundred thirty-three".