61985261 has 4 divisors (see below), whose sum is σ = 66753372. Its totient is φ = 57217152.

The previous prime is 61985237. The next prime is 61985263. The reversal of 61985261 is 16258916.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16152361 + 45832900 = 4019^2 + 6770^2 .

It is a cyclic number.

It is not a de Polignac number, because 61985261 - 2⁶ = 61985197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61985263) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2384036 + ... + 2384061.

It is an arithmetic number, because the mean of its divisors is an integer number (16688343).

Almost surely, 2^61985261 is an apocalyptic number.

It is an amenable number.

61985261 is a deficient number, since it is larger than the sum of its proper divisors (4768111).

61985261 is a wasteful number, since it uses less digits than its factorization.

61985261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4768110.

The product of its digits is 25920, while the sum is 38.

The square root of 61985261 is about 7873.0718909457. The cubic root of 61985261 is about 395.7577953833.

The spelling of 61985261 in words is "sixty-one million, nine hundred eighty-five thousand, two hundred sixty-one".