661248089 has 16 divisors (see below), whose sum is σ = 711998400. Its totient is φ = 612251136.

The previous prime is 661248083. The next prime is 661248101. The reversal of 661248089 is 980842166.

It is a happy number.

It is not a de Polignac number, because 661248089 - 2⁸ = 661247833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (661248083) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 154622 + ... + 158840.

It is an arithmetic number, because the mean of its divisors is an integer number (44499900).

Almost surely, 2^661248089 is an apocalyptic number.

It is an amenable number.

661248089 is a deficient number, since it is larger than the sum of its proper divisors (50750311).

661248089 is a wasteful number, since it uses less digits than its factorization.

661248089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4424.

The product of its (nonzero) digits is 165888, while the sum is 44.

The square root of 661248089 is about 25714.7445836042. The cubic root of 661248089 is about 871.2072415302.

The spelling of 661248089 in words is "six hundred sixty-one million, two hundred forty-eight thousand, eighty-nine".