1989551616 has 160 divisors (see below), whose sum is σ = 6044800608. Its totient is φ = 576061440.

The previous prime is 1989551593. The next prime is 1989551621. The reversal of 1989551616 is 6161559891.

It is a super-2 number, since 2×1989551616² = 7916631265456422912, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 336526 + ... + 342386.

Almost surely, 2^1989551616 is an apocalyptic number.

1989551616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1989551616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3022400304).

1989551616 is an abundant number, since it is smaller than the sum of its proper divisors (4055248992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1989551616 is a wasteful number, since it uses less digits than its factorization.

1989551616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5912 (or 5896 counting only the distinct ones).

The product of its digits is 583200, while the sum is 51.

The square root of 1989551616 is about 44604.3900978368. The cubic root of 1989551616 is about 1257.7231949447.

The spelling of 1989551616 in words is "one billion, nine hundred eighty-nine million, five hundred fifty-one thousand, six hundred sixteen".