1990961910 has 128 divisors (see below), whose sum is σ = 6079656960. Its totient is φ = 454180608.

The previous prime is 1990961909. The next prime is 1990961939. The reversal of 1990961910 is 191690991.

1990961910 is a `hidden beast` number, since 19 + 9 + 0 + 9 + 619 + 10 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1668274 + ... + 1669466.

It is an arithmetic number, because the mean of its divisors is an integer number (47497320).

Almost surely, 2^1990961910 is an apocalyptic number.

1990961910 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1990961910, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3039828480).

1990961910 is an abundant number, since it is smaller than the sum of its proper divisors (4088695050).

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

1990961910 is a wasteful number, since it uses less digits than its factorization.

1990961910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2099 (or 2093 counting only the distinct ones).

The product of its (nonzero) digits is 39366, while the sum is 45.

The square root of 1990961910 is about 44620.1962120294. The cubic root of 1990961910 is about 1258.0203038538.

The spelling of 1990961910 in words is "one billion, nine hundred ninety million, nine hundred sixty-one thousand, nine hundred ten".