61531585 has 8 divisors (see below), whose sum is σ = 78181416. Its totient is φ = 46329600.

The previous prime is 61531583. The next prime is 61531607. The reversal of 61531585 is 58513516.

It can be written as a sum of positive squares in 4 ways, for example, as 1577536 + 59954049 = 1256^2 + 7743^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61531585 - 2¹ = 61531583 is a prime.

It is a super-2 number, since 2×61531585² = 7572271905224450, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61531585.

It is not an unprimeable number, because it can be changed into a prime (61531583) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 361866 + ... + 362035.

It is an arithmetic number, because the mean of its divisors is an integer number (9772677).

Almost surely, 2^61531585 is an apocalyptic number.

It is an amenable number.

61531585 is a deficient number, since it is larger than the sum of its proper divisors (16649831).

61531585 is a wasteful number, since it uses less digits than its factorization.

61531585 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 723923.

The product of its digits is 18000, while the sum is 34.

The square root of 61531585 is about 7844.2070982350. The cubic root of 61531585 is about 394.7899005528.

The spelling of 61531585 in words is "sixty-one million, five hundred thirty-one thousand, five hundred eighty-five".