396977909 has 4 divisors (see below), whose sum is σ = 409783680. Its totient is φ = 384172140.

The previous prime is 396977879. The next prime is 396977941. The reversal of 396977909 is 909779693.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 909779693 = 6043 ⋅150551.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-396977909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (396977989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6402839 + ... + 6402900.

It is an arithmetic number, because the mean of its divisors is an integer number (102445920).

Almost surely, 2^396977909 is an apocalyptic number.

It is an amenable number.

396977909 is a deficient number, since it is larger than the sum of its proper divisors (12805771).

396977909 is a wasteful number, since it uses less digits than its factorization.

396977909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12805770.

The product of its (nonzero) digits is 5786802, while the sum is 59.

The square root of 396977909 is about 19924.3044797052. The cubic root of 396977909 is about 734.9460271657.

The spelling of 396977909 in words is "three hundred ninety-six million, nine hundred seventy-seven thousand, nine hundred nine".