61891669 has 8 divisors (see below), whose sum is σ = 70781120. Its totient is φ = 53014176.

The previous prime is 61891657. The next prime is 61891693. The reversal of 61891669 is 96619816.

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 61891669 - 2¹⁷ = 61760597 is a prime.

It is a super-2 number, since 2×61891669² = 7661157383211122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61891619) 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, 17362 + ... + 20620.

It is an arithmetic number, because the mean of its divisors is an integer number (8847640).

Almost surely, 2^61891669 is an apocalyptic number.

It is an amenable number.

61891669 is a deficient number, since it is larger than the sum of its proper divisors (8889451).

61891669 is a wasteful number, since it uses less digits than its factorization.

61891669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5979.

The product of its digits is 139968, while the sum is 46.

The square root of 61891669 is about 7867.1258411189. The cubic root of 61891669 is about 395.5585091828.

The spelling of 61891669 in words is "sixty-one million, eight hundred ninety-one thousand, six hundred sixty-nine".