402669 has 6 divisors (see below), whose sum is σ = 581646. Its totient is φ = 268440.

The previous prime is 402631. The next prime is 402691. The reversal of 402669 is 966204.

It can be written as a sum of positive squares in only one way, i.e., 213444 + 189225 = 462^2 + 435^2 .

It is not a de Polignac number, because 402669 - 2⁷ = 402541 is a prime.

It is a super-2 number, since 2×402669² = 324284647122, which contains 22 as substring.

It is a Curzon number.

402669 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402769) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 22362 + ... + 22379.

It is an arithmetic number, because the mean of its divisors is an integer number (96941).

2⁴⁰²⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

402669 is a deficient number, since it is larger than the sum of its proper divisors (178977).

402669 is a wasteful number, since it uses less digits than its factorization.

402669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44747 (or 44744 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 402669 is about 634.5620537032. The cubic root of 402669 is about 73.8441448272.

It can be divided in two parts, 4026 and 69, that added together give a triangular number (4095 = T₉₀).

The spelling of 402669 in words is "four hundred two thousand, six hundred sixty-nine".