1978051892 has 12 divisors (see below), whose sum is σ = 3492225156. Its totient is φ = 980273280.

The previous prime is 1978051879. The next prime is 1978051903. The reversal of 1978051892 is 2981508791.

It can be written as a sum of positive squares in 2 ways, for example, as 246992656 + 1731059236 = 15716^2 + 41606^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1978051892.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2187659 + ... + 2188562.

It is an arithmetic number, because the mean of its divisors is an integer number (291018763).

Almost surely, 2^1978051892 is an apocalyptic number.

It is an amenable number.

1978051892 is a deficient number, since it is larger than the sum of its proper divisors (1514173264).

1978051892 is a wasteful number, since it uses less digits than its factorization.

1978051892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4376338 (or 4376336 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 50.

The square root of 1978051892 is about 44475.2952997504. The cubic root of 1978051892 is about 1255.2952733486.

The spelling of 1978051892 in words is "one billion, nine hundred seventy-eight million, fifty-one thousand, eight hundred ninety-two".