1981622740 has 24 divisors (see below), whose sum is σ = 4165281792. Its totient is φ = 791911200.

The previous prime is 1981622737. The next prime is 1981622761. The reversal of 1981622740 is 472261891.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 1981622693 and 1981622702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23836 + ... + 67315.

It is an arithmetic number, because the mean of its divisors is an integer number (173553408).

Almost surely, 2^1981622740 is an apocalyptic number.

1981622740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1981622740 is an abundant number, since it is smaller than the sum of its proper divisors (2183659052).

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

1981622740 is a wasteful number, since it uses less digits than its factorization.

1981622740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92247 (or 92245 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 1981622740 is about 44515.4213728231. The cubic root of 1981622740 is about 1256.0501868123.

The spelling of 1981622740 in words is "one billion, nine hundred eighty-one million, six hundred twenty-two thousand, seven hundred forty".