43091992978 has 4 divisors (see below), whose sum is σ = 64637989470. Its totient is φ = 21545996488.

The previous prime is 43091992949. The next prime is 43091992981. The reversal of 43091992978 is 87929919034.

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., 34896855249 + 8195137729 = 186807^2 + 90527^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10772998243 + ... + 10772998246.

Almost surely, 2^43091992978 is an apocalyptic number.

43091992978 is a deficient number, since it is larger than the sum of its proper divisors (21545996492).

43091992978 is a wasteful number, since it uses less digits than its factorization.

43091992978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21545996491.

The product of its (nonzero) digits is 8817984, while the sum is 61.

The spelling of 43091992978 in words is "forty-three billion, ninety-one million, nine hundred ninety-two thousand, nine hundred seventy-eight".