139421989 has 16 divisors (see below), whose sum is σ = 161981568. Its totient is φ = 117536832.

The previous prime is 139421983. The next prime is 139421993. The reversal of 139421989 is 989124931.

It is a happy number.

It is not a de Polignac number, because 139421989 - 2⁷ = 139421861 is a prime.

It is a super-2 number, since 2×139421989² = 38876982033432242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139421983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 183799 + ... + 184555.

It is an arithmetic number, because the mean of its divisors is an integer number (10123848).

Almost surely, 2^139421989 is an apocalyptic number.

It is an amenable number.

139421989 is a deficient number, since it is larger than the sum of its proper divisors (22559579).

139421989 is an equidigital number, since it uses as much as digits as its factorization.

139421989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1164.

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

The square root of 139421989 is about 11807.7088802189. The cubic root of 139421989 is about 518.5338247867.

It can be divided in two parts, 13942 and 1989, that added together give a triangular number (15931 = T₁₇₈).

The spelling of 139421989 in words is "one hundred thirty-nine million, four hundred twenty-one thousand, nine hundred eighty-nine".