61560021 has 8 divisors (see below), whose sum is σ = 83069280. Its totient is φ = 40545392.

The previous prime is 61560013. The next prime is 61560049. The reversal of 61560021 is 12006516.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 61560021 - 2³ = 61560013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61560021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61560001) 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, 123366 + ... + 123863.

It is an arithmetic number, because the mean of its divisors is an integer number (10383660).

Almost surely, 2^61560021 is an apocalyptic number.

It is an amenable number.

61560021 is a deficient number, since it is larger than the sum of its proper divisors (21509259).

61560021 is a wasteful number, since it uses less digits than its factorization.

61560021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247315.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 61560021 is about 7846.0194366315. The cubic root of 61560021 is about 394.8507068130.

Adding to 61560021 its reverse (12006516), we get a palindrome (73566537).

The spelling of 61560021 in words is "sixty-one million, five hundred sixty thousand, twenty-one".