661151567 has 2 divisors, whose sum is σ = 661151568. Its totient is φ = 661151566.

The previous prime is 661151563. The next prime is 661151593. The reversal of 661151567 is 765151166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661151567 - 2² = 661151563 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661151567.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661151563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330575783 + 330575784.

It is an arithmetic number, because the mean of its divisors is an integer number (330575784).

Almost surely, 2^661151567 is an apocalyptic number.

661151567 is a deficient number, since it is larger than the sum of its proper divisors (1).

661151567 is an equidigital number, since it uses as much as digits as its factorization.

661151567 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37800, while the sum is 38.

The square root of 661151567 is about 25712.8677319353. The cubic root of 661151567 is about 871.1648495956.

The spelling of 661151567 in words is "six hundred sixty-one million, one hundred fifty-one thousand, five hundred sixty-seven".