3973978 has 4 divisors (see below), whose sum is σ = 5960970. Its totient is φ = 1986988.

The previous prime is 3973973. The next prime is 3973997. The reversal of 3973978 is 8793793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8793793 = 109 ⋅80677.

It can be written as a sum of positive squares in only one way, i.e., 3229209 + 744769 = 1797^2 + 863^2 .

It is a super-2 number, since 2×3973978² = 31585002288968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (3973973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993493 + ... + 993496.

Almost surely, 2^3973978 is an apocalyptic number.

3973978 is a deficient number, since it is larger than the sum of its proper divisors (1986992).

3973978 is a wasteful number, since it uses less digits than its factorization.

3973978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1986991.

The product of its digits is 285768, while the sum is 46.

The square root of 3973978 is about 1993.4838850615. The cubic root of 3973978 is about 158.3951281109.

The spelling of 3973978 in words is "three million, nine hundred seventy-three thousand, nine hundred seventy-eight".