1978681724 has 6 divisors (see below), whose sum is σ = 3462693024. Its totient is φ = 989340860.

The previous prime is 1978681709. The next prime is 1978681729. The reversal of 1978681724 is 4271868791.

It is a happy number.

It is a super-2 number, since 2×1978681724² = 7830362729783224352, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1978681729) by changing a digit.

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 as a sum of consecutive naturals, namely, 247335212 + ... + 247335219.

It is an arithmetic number, because the mean of its divisors is an integer number (577115504).

Almost surely, 2^1978681724 is an apocalyptic number.

It is an amenable number.

1978681724 is a deficient number, since it is larger than the sum of its proper divisors (1484011300).

1978681724 is a wasteful number, since it uses less digits than its factorization.

1978681724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494670435 (or 494670433 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 53.

The square root of 1978681724 is about 44482.3754311750. The cubic root of 1978681724 is about 1255.4284921713.

The spelling of 1978681724 in words is "one billion, nine hundred seventy-eight million, six hundred eighty-one thousand, seven hundred twenty-four".