1978929842 has 4 divisors (see below), whose sum is σ = 2968394766. Its totient is φ = 989464920.

The previous prime is 1978929839. The next prime is 1978929871. The reversal of 1978929842 is 2489298791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1955319961 + 23609881 = 44219^2 + 4859^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 494732459 + ... + 494732462.

Almost surely, 2^1978929842 is an apocalyptic number.

1978929842 is a deficient number, since it is larger than the sum of its proper divisors (989464924).

1978929842 is an equidigital number, since it uses as much as digits as its factorization.

1978929842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989464923.

The product of its digits is 5225472, while the sum is 59.

The square root of 1978929842 is about 44485.1642910308. The cubic root of 1978929842 is about 1255.4809650516.

The spelling of 1978929842 in words is "one billion, nine hundred seventy-eight million, nine hundred twenty-nine thousand, eight hundred forty-two".