61789989 has 4 divisors (see below), whose sum is σ = 82386656. Its totient is φ = 41193324.

The previous prime is 61789979. The next prime is 61789991. The reversal of 61789989 is 98998716.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 61789989 - 2⁸ = 61789733 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 (61789909) 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, 10298329 + ... + 10298334.

It is an arithmetic number, because the mean of its divisors is an integer number (20596664).

Almost surely, 2^61789989 is an apocalyptic number.

It is an amenable number.

61789989 is a deficient number, since it is larger than the sum of its proper divisors (20596667).

61789989 is a wasteful number, since it uses less digits than its factorization.

61789989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20596666.

The product of its digits is 1959552, while the sum is 57.

The square root of 61789989 is about 7860.6608500812. The cubic root of 61789989 is about 395.3417733086.

The spelling of 61789989 in words is "sixty-one million, seven hundred eighty-nine thousand, nine hundred eighty-nine".