61998879 has 4 divisors (see below), whose sum is σ = 82665176. Its totient is φ = 41332584.

The previous prime is 61998877. The next prime is 61998883. The reversal of 61998879 is 97889916.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 61998879 - 2¹ = 61998877 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 (61998877) 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, 10333144 + ... + 10333149.

It is an arithmetic number, because the mean of its divisors is an integer number (20666294).

Almost surely, 2^61998879 is an apocalyptic number.

61998879 is a deficient number, since it is larger than the sum of its proper divisors (20666297).

61998879 is a wasteful number, since it uses less digits than its factorization.

61998879 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20666296.

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

The square root of 61998879 is about 7873.9366901189. The cubic root of 61998879 is about 395.7867755792.

The spelling of 61998879 in words is "sixty-one million, nine hundred ninety-eight thousand, eight hundred seventy-nine".