1981954922 has 4 divisors (see below), whose sum is σ = 2972932386. Its totient is φ = 990977460.

The previous prime is 1981954903. The next prime is 1981954967. The reversal of 1981954922 is 2294591891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2294591891 = 467 ⋅4913473.

It can be written as a sum of positive squares in only one way, i.e., 1965946921 + 16008001 = 44339^2 + 4001^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495488729 + ... + 495488732.

Almost surely, 2^1981954922 is an apocalyptic number.

1981954922 is a deficient number, since it is larger than the sum of its proper divisors (990977464).

1981954922 is an equidigital number, since it uses as much as digits as its factorization.

1981954922 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 990977463.

The product of its digits is 466560, while the sum is 50.

The square root of 1981954922 is about 44519.1523054966. The cubic root of 1981954922 is about 1256.1203673337.

The spelling of 1981954922 in words is "one billion, nine hundred eighty-one million, nine hundred fifty-four thousand, nine hundred twenty-two".