406191989 has 8 divisors (see below), whose sum is σ = 471148608. Its totient is φ = 342967680.

The previous prime is 406191979. The next prime is 406192019. The reversal of 406191989 is 989191604.

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

It is a cyclic number.

It is not a de Polignac number, because 406191989 - 2²⁸ = 137756533 is a prime.

It is a super-2 number, since 2×406191989² = 329983863855552242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (406191979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 432572 + ... + 433509.

It is an arithmetic number, because the mean of its divisors is an integer number (58893576).

Almost surely, 2^406191989 is an apocalyptic number.

It is an amenable number.

406191989 is a deficient number, since it is larger than the sum of its proper divisors (64956619).

406191989 is an equidigital number, since it uses as much as digits as its factorization.

406191989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 866155.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 406191989 is about 20154.2052435714. The cubic root of 406191989 is about 740.5887626320.

The spelling of 406191989 in words is "four hundred six million, one hundred ninety-one thousand, nine hundred eighty-nine".