1621089698 has 4 divisors (see below), whose sum is σ = 2431634550. Its totient is φ = 810544848.

The previous prime is 1621089661. The next prime is 1621089713. The reversal of 1621089698 is 8969801261.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 1552911649 + 68178049 = 39407^2 + 8257^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405272423 + ... + 405272426.

Almost surely, 2^1621089698 is an apocalyptic number.

1621089698 is a deficient number, since it is larger than the sum of its proper divisors (810544852).

1621089698 is an equidigital number, since it uses as much as digits as its factorization.

1621089698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 810544851.

The product of its (nonzero) digits is 373248, while the sum is 50.

The square root of 1621089698 is about 40262.7582015937. The cubic root of 1621089698 is about 1174.7235681086.

The spelling of 1621089698 in words is "one billion, six hundred twenty-one million, eighty-nine thousand, six hundred ninety-eight".