3999562978 has 8 divisors (see below), whose sum is σ = 6013201068. Its totient is φ = 1995162624.

The previous prime is 3999562969. The next prime is 3999562981. The reversal of 3999562978 is 8792659993.

It can be written as a sum of positive squares in 2 ways, for example, as 3998918169 + 644809 = 63237^2 + 803^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 2308351 + ... + 2310082.

Almost surely, 2^3999562978 is an apocalyptic number.

3999562978 is a deficient number, since it is larger than the sum of its proper divisors (2013638090).

3999562978 is a wasteful number, since it uses less digits than its factorization.

3999562978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4618868.

The product of its digits is 66134880, while the sum is 67.

The square root of 3999562978 is about 63242.0981467250. The cubic root of 3999562978 is about 1587.3432390975.

The spelling of 3999562978 in words is "three billion, nine hundred ninety-nine million, five hundred sixty-two thousand, nine hundred seventy-eight".