• 402 can be written using four 4's:

See also 113.

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402 has 8 divisors (see below), whose sum is σ = 816. Its totient is φ = 132.

The previous prime is 401. The next prime is 409. The reversal of 402 is 204.

It is a sphenic number, since it is the product of 3 distinct primes.

402 is an admirable number.

It is a Harshad number since it is a multiple of its sum of digits (6), and also a Moran number because the ratio is a prime number: 67 = 402 / (4 + 0 + 2).

It is an Ulam number.

It is a plaindrome in base 7, base 11, base 13 and base 15.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (401) 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, 28 + ... + 39.

It is an arithmetic number, because the mean of its divisors is an integer number (102).

402 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (408).

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

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

The sum of its prime factors is 72.

The product of its (nonzero) digits is 8, while the sum is 6.

The square root of 402 is about 20.0499376558. The cubic root of 402 is about 7.3803226921.

Adding to 402 its reverse (204), we get a palindrome (606).

The spelling of 402 in words is "four hundred two", and thus it is an aban number and an iban number.