402002191 has 4 divisors (see below), whose sum is σ = 409587192. Its totient is φ = 394417192.

The previous prime is 402002177. The next prime is 402002197. The reversal of 402002191 is 191200204.

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

It is a cyclic number.

It is not a de Polignac number, because 402002191 - 2¹⁵ = 401969423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402002197) 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, 3792421 + ... + 3792526.

It is an arithmetic number, because the mean of its divisors is an integer number (102396798).

Almost surely, 2^402002191 is an apocalyptic number.

402002191 is a deficient number, since it is larger than the sum of its proper divisors (7585001).

402002191 is an equidigital number, since it uses as much as digits as its factorization.

402002191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7585000.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 402002191 is about 20049.9922942629. The cubic root of 402002191 is about 738.0336100272.

Adding to 402002191 its reverse (191200204), we get a palindrome (593202395).

The spelling of 402002191 in words is "four hundred two million, two thousand, one hundred ninety-one".