661700125 has 32 divisors (see below), whose sum is σ = 849873024. Its totient is φ = 514080000.

The previous prime is 661700113. The next prime is 661700173. The reversal of 661700125 is 521007166.

It is not a de Polignac number, because 661700125 - 2¹¹ = 661698077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661700093 and 661700102.

It is a congruent number.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 1649925 + ... + 1650325.

It is an arithmetic number, because the mean of its divisors is an integer number (26558532).

Almost surely, 2^661700125 is an apocalyptic number.

It is an amenable number.

661700125 is a deficient number, since it is larger than the sum of its proper divisors (188172899).

661700125 is a wasteful number, since it uses less digits than its factorization.

661700125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 766 (or 756 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 661700125 is about 25723.5325140230. The cubic root of 661700125 is about 871.4057183894.

It can be divided in two parts, 661700 and 125, that added together give a triangular number (661825 = T₁₁₅₀).

The spelling of 661700125 in words is "six hundred sixty-one million, seven hundred thousand, one hundred twenty-five".