61853661 has 6 divisors (see below), whose sum is σ = 89344190. Its totient is φ = 41235768.

The previous prime is 61853657. The next prime is 61853669. The reversal of 61853661 is 16635816.

It is a happy number.

61853661 is a `hidden beast` number, since 61 + 8 + 536 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 55041561 + 6812100 = 7419^2 + 2610^2 .

It is not a de Polignac number, because 61853661 - 2² = 61853657 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 (61853669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3436306 + ... + 3436323.

Almost surely, 2^61853661 is an apocalyptic number.

It is an amenable number.

61853661 is a deficient number, since it is larger than the sum of its proper divisors (27490529).

61853661 is a wasteful number, since it uses less digits than its factorization.

61853661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6872635 (or 6872632 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 61853661 is about 7864.7098484305. The cubic root of 61853661 is about 395.4775210807.

The spelling of 61853661 in words is "sixty-one million, eight hundred fifty-three thousand, six hundred sixty-one".