101978989 has 4 divisors (see below), whose sum is σ = 116547424. Its totient is φ = 87410556.

The previous prime is 101978951. The next prime is 101978999. The reversal of 101978989 is 989879101.

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 a cyclic number.

It is not a de Polignac number, because 101978989 - 2¹³ = 101970797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101978939) 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, 7284207 + ... + 7284220.

It is an arithmetic number, because the mean of its divisors is an integer number (29136856).

Almost surely, 2^101978989 is an apocalyptic number.

It is an amenable number.

101978989 is a deficient number, since it is larger than the sum of its proper divisors (14568435).

101978989 is an equidigital number, since it uses as much as digits as its factorization.

101978989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14568434.

The product of its (nonzero) digits is 326592, while the sum is 52.

The square root of 101978989 is about 10098.4646852876. The cubic root of 101978989 is about 467.2007888354.

It can be divided in two parts, 1019 and 78989, that added together give a palindrome (80008).

The spelling of 101978989 in words is "one hundred one million, nine hundred seventy-eight thousand, nine hundred eighty-nine".