661532453 has 2 divisors, whose sum is σ = 661532454. Its totient is φ = 661532452.

The previous prime is 661532449. The next prime is 661532471. The reversal of 661532453 is 354235166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 610238209 + 51294244 = 24703^2 + 7162^2 .

It is a cyclic number.

It is not a de Polignac number, because 661532453 - 2² = 661532449 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661532413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330766226 + 330766227.

It is an arithmetic number, because the mean of its divisors is an integer number (330766227).

Almost surely, 2^661532453 is an apocalyptic number.

It is an amenable number.

661532453 is a deficient number, since it is larger than the sum of its proper divisors (1).

661532453 is an equidigital number, since it uses as much as digits as its factorization.

661532453 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64800, while the sum is 35.

The square root of 661532453 is about 25720.2731906176. The cubic root of 661532453 is about 871.3321086695.

The spelling of 661532453 in words is "six hundred sixty-one million, five hundred thirty-two thousand, four hundred fifty-three".