1988739 has 16 divisors (see below), whose sum is σ = 2989600. Its totient is φ = 1306368.

The previous prime is 1988729. The next prime is 1988759. The reversal of 1988739 is 9378891.

It is not a de Polignac number, because 1988739 - 2⁷ = 1988611 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1988694 and 1988703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1988729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1467 + ... + 2475.

It is an arithmetic number, because the mean of its divisors is an integer number (186850).

2^1988739 is an apocalyptic number.

1988739 is a deficient number, since it is larger than the sum of its proper divisors (1000861).

1988739 is a wasteful number, since it uses less digits than its factorization.

1988739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1091 (or 1085 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 1988739 is about 1410.2265775399. The cubic root of 1988739 is about 125.7551936060.

The spelling of 1988739 in words is "one million, nine hundred eighty-eight thousand, seven hundred thirty-nine".