1921737988 has 24 divisors (see below), whose sum is σ = 3475180800. Its totient is φ = 928894560.

The previous prime is 1921737977. The next prime is 1921737991. The reversal of 1921737988 is 8897371291.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117963 + ... + 133261.

It is an arithmetic number, because the mean of its divisors is an integer number (144799200).

Almost surely, 2^1921737988 is an apocalyptic number.

It is an amenable number.

1921737988 is a deficient number, since it is larger than the sum of its proper divisors (1553442812).

1921737988 is a wasteful number, since it uses less digits than its factorization.

1921737988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16347 (or 16345 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 55.

The square root of 1921737988 is about 43837.6320984608. The cubic root of 1921737988 is about 1243.2679123929.

It can be divided in two parts, 192 and 1737988, that added together give a triangular number (1738180 = T₁₈₆₄).

The spelling of 1921737988 in words is "one billion, nine hundred twenty-one million, seven hundred thirty-seven thousand, nine hundred eighty-eight".