402501689 has 4 divisors (see below), whose sum is σ = 403581156. Its totient is φ = 401422224.

The previous prime is 402501677. The next prime is 402501703. The reversal of 402501689 is 986105204.

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 68343289 + 334158400 = 8267^2 + 18280^2 .

It is a cyclic number.

It is not a de Polignac number, because 402501689 - 2⁸ = 402501433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402501289) 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, 539174 + ... + 539919.

It is an arithmetic number, because the mean of its divisors is an integer number (100895289).

Almost surely, 2^402501689 is an apocalyptic number.

It is an amenable number.

402501689 is a deficient number, since it is larger than the sum of its proper divisors (1079467).

402501689 is a wasteful number, since it uses less digits than its factorization.

402501689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1079466.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 402501689 is about 20062.4447413569. Note that the first 3 decimals coincide. The cubic root of 402501689 is about 738.3391587212.

The spelling of 402501689 in words is "four hundred two million, five hundred one thousand, six hundred eighty-nine".