616661525 has 24 divisors (see below), whose sum is σ = 786465288. Its totient is φ = 479360000.

The previous prime is 616661503. The next prime is 616661527. The reversal of 616661525 is 525166616.

It can be written as a sum of positive squares in 12 ways, for example, as 113018161 + 503643364 = 10631^2 + 22442^2 .

It is not a de Polignac number, because 616661525 - 2¹⁰ = 616660501 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (616661527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 286955 + ... + 289095.

It is an arithmetic number, because the mean of its divisors is an integer number (32769387).

Almost surely, 2^616661525 is an apocalyptic number.

It is an amenable number.

616661525 is a deficient number, since it is larger than the sum of its proper divisors (169803763).

616661525 is a wasteful number, since it uses less digits than its factorization.

616661525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2473 (or 2468 counting only the distinct ones).

The product of its digits is 64800, while the sum is 38.

The square root of 616661525 is about 24832.6705168816. The cubic root of 616661525 is about 851.1686462662.

The spelling of 616661525 in words is "six hundred sixteen million, six hundred sixty-one thousand, five hundred twenty-five".