1642661898 has 8 divisors (see below), whose sum is σ = 3285323808. Its totient is φ = 547553964.

The previous prime is 1642661869. The next prime is 1642661939. The reversal of 1642661898 is 8981662461.

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

1642661898 is an admirable number.

It is a super-2 number, since 2×1642661898² = 5396676222281924808, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1642661898.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136888486 + ... + 136888497.

It is an arithmetic number, because the mean of its divisors is an integer number (410665476).

Almost surely, 2^1642661898 is an apocalyptic number.

1642661898 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.

1642661898 is a wasteful number, since it uses less digits than its factorization.

1642661898 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273776988.

The product of its digits is 995328, while the sum is 51.

The square root of 1642661898 is about 40529.7655803731. The cubic root of 1642661898 is about 1179.9113928486.

The spelling of 1642661898 in words is "one billion, six hundred forty-two million, six hundred sixty-one thousand, eight hundred ninety-eight".