396642749 has 4 divisors (see below), whose sum is σ = 398186364. Its totient is φ = 395099136.

The previous prime is 396642721. The next prime is 396642767. The reversal of 396642749 is 947246693.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 309126724 + 87516025 = 17582^2 + 9355^2 .

It is a cyclic number.

It is not a de Polignac number, because 396642749 - 2¹⁶ = 396577213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 396642697 and 396642706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (396642349) 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, 771422 + ... + 771935.

It is an arithmetic number, because the mean of its divisors is an integer number (99546591).

Almost surely, 2^396642749 is an apocalyptic number.

It is an amenable number.

396642749 is a deficient number, since it is larger than the sum of its proper divisors (1543615).

396642749 is a wasteful number, since it uses less digits than its factorization.

396642749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1543614.

The product of its digits is 1959552, while the sum is 50.

The square root of 396642749 is about 19915.8918705641. The cubic root of 396642749 is about 734.7391358337.

The spelling of 396642749 in words is "three hundred ninety-six million, six hundred forty-two thousand, seven hundred forty-nine".