1961555000 has 160 divisors (see below), whose sum is σ = 4936044960. Its totient is φ = 728640000.

The previous prime is 1961554999. The next prime is 1961555021. The reversal of 1961555000 is 5551691.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4254770 + ... + 4255230.

It is an arithmetic number, because the mean of its divisors is an integer number (30850281).

Almost surely, 2^1961555000 is an apocalyptic number.

1961555000 is a gapful number since it is divisible by the number (10) 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 1961555000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2468022480).

1961555000 is an abundant number, since it is smaller than the sum of its proper divisors (2974489960).

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

1961555000 is a wasteful number, since it uses less digits than its factorization.

1961555000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547 (or 528 counting only the distinct ones).

The product of its (nonzero) digits is 6750, while the sum is 32.

The square root of 1961555000 is about 44289.4456953347. The cubic root of 1961555000 is about 1251.7958187924.

The spelling of 1961555000 in words is "one billion, nine hundred sixty-one million, five hundred fifty-five thousand".