20998351 has 8 divisors (see below), whose sum is σ = 23526864. Its totient is φ = 18573120.

The previous prime is 20998303. The next prime is 20998387. The reversal of 20998351 is 15389902.

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 20998351 - 2⁷ = 20998223 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20998351.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20998051) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 25390 + ... + 26203.

It is an arithmetic number, because the mean of its divisors is an integer number (2940858).

Almost surely, 2^20998351 is an apocalyptic number.

20998351 is a deficient number, since it is larger than the sum of its proper divisors (2528513).

20998351 is a wasteful number, since it uses less digits than its factorization.

20998351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51641.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 20998351 is about 4582.3957707732. The cubic root of 20998351 is about 275.8851960745.

The spelling of 20998351 in words is "twenty million, nine hundred ninety-eight thousand, three hundred fifty-one".