1991954730 has 32 divisors (see below), whose sum is σ = 4783855104. Its totient is φ = 530836416.

The previous prime is 1991954729. The next prime is 1991954749. The reversal of 1991954730 is 374591991.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 1991954730.

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 15 ways as a sum of consecutive naturals, for example, 25824 + ... + 68196.

It is an arithmetic number, because the mean of its divisors is an integer number (149495472).

Almost surely, 2^1991954730 is an apocalyptic number.

1991954730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1991954730 is an abundant number, since it is smaller than the sum of its proper divisors (2791900374).

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

1991954730 is a wasteful number, since it uses less digits than its factorization.

1991954730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43950.

The product of its (nonzero) digits is 306180, while the sum is 48.

The square root of 1991954730 is about 44631.3200566598. The cubic root of 1991954730 is about 1258.2293787003.

The spelling of 1991954730 in words is "one billion, nine hundred ninety-one million, nine hundred fifty-four thousand, seven hundred thirty".