397639243 has 2 divisors, whose sum is σ = 397639244. Its totient is φ = 397639242.

The previous prime is 397639217. The next prime is 397639267. The reversal of 397639243 is 342936793.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 397639243 - 2⁵ = 397639211 is a prime.

It is a super-2 number, since 2×397639243² = 316233935147226098, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 397639193 and 397639202.

It is not a weakly prime, because it can be changed into another prime (397639283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198819621 + 198819622.

It is an arithmetic number, because the mean of its divisors is an integer number (198819622).

Almost surely, 2^397639243 is an apocalyptic number.

397639243 is a deficient number, since it is larger than the sum of its proper divisors (1).

397639243 is an equidigital number, since it uses as much as digits as its factorization.

397639243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 734832, while the sum is 46.

The square root of 397639243 is about 19940.8937362396. The cubic root of 397639243 is about 735.3539215181.

The spelling of 397639243 in words is "three hundred ninety-seven million, six hundred thirty-nine thousand, two hundred forty-three".