5645297978 has 4 divisors (see below), whose sum is σ = 8467946970. Its totient is φ = 2822648988.

The previous prime is 5645297953. The next prime is 5645298017. The reversal of 5645297978 is 8797925465.

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., 5357215249 + 288082729 = 73193^2 + 16973^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 5645297978.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1411324493 + ... + 1411324496.

Almost surely, 2^5645297978 is an apocalyptic number.

5645297978 is a deficient number, since it is larger than the sum of its proper divisors (2822648992).

5645297978 is a wasteful number, since it uses less digits than its factorization.

5645297978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2822648991.

The product of its digits is 38102400, while the sum is 62.

The square root of 5645297978 is about 75135.1979966780. The cubic root of 5645297978 is about 1780.5832766350.

The spelling of 5645297978 in words is "five billion, six hundred forty-five million, two hundred ninety-seven thousand, nine hundred seventy-eight".