661264075 has 6 divisors (see below), whose sum is σ = 819967484. Its totient is φ = 529011240.

The previous prime is 661264063. The next prime is 661264081. The reversal of 661264075 is 570462166.

It is a happy number.

It is not a de Polignac number, because 661264075 - 2⁷ = 661263947 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13225257 + ... + 13225306.

Almost surely, 2^661264075 is an apocalyptic number.

661264075 is a deficient number, since it is larger than the sum of its proper divisors (158703409).

661264075 is a wasteful number, since it uses less digits than its factorization.

661264075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26450573 (or 26450568 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 661264075 is about 25715.0554150676. The cubic root of 661264075 is about 871.2142620958.

The spelling of 661264075 in words is "six hundred sixty-one million, two hundred sixty-four thousand, seventy-five".