661954825 has 24 divisors (see below), whose sum is σ = 949978880. Its totient is φ = 448156800.

The previous prime is 661954801. The next prime is 661954831. The reversal of 661954825 is 528459166.

It is not a de Polignac number, because 661954825 - 2¹¹ = 661952777 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10116 + ... + 37765.

Almost surely, 2^661954825 is an apocalyptic number.

It is an amenable number.

661954825 is a deficient number, since it is larger than the sum of its proper divisors (288024055).

661954825 is a wasteful number, since it uses less digits than its factorization.

661954825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47977 (or 47972 counting only the distinct ones).

The product of its digits is 518400, while the sum is 46.

The square root of 661954825 is about 25728.4827574422. The cubic root of 661954825 is about 871.5175105024.

The spelling of 661954825 in words is "six hundred sixty-one million, nine hundred fifty-four thousand, eight hundred twenty-five".