61891647 has 8 divisors (see below), whose sum is σ = 82596144. Its totient is φ = 41224128.

The previous prime is 61891633. The next prime is 61891657. The reversal of 61891647 is 74619816.

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

It is not a de Polignac number, because 61891647 - 2⁸ = 61891391 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 61891599 and 61891608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61891657) 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, 5068 + ... + 12225.

It is an arithmetic number, because the mean of its divisors is an integer number (10324518).

Almost surely, 2^61891647 is an apocalyptic number.

61891647 is a deficient number, since it is larger than the sum of its proper divisors (20704497).

61891647 is a wasteful number, since it uses less digits than its factorization.

61891647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18489.

The product of its digits is 72576, while the sum is 42.

The square root of 61891647 is about 7867.1244428953. The cubic root of 61891647 is about 395.5584623145.

The spelling of 61891647 in words is "sixty-one million, eight hundred ninety-one thousand, six hundred forty-seven".