20499999 has 8 divisors (see below), whose sum is σ = 29435952. Its totient is φ = 12615360.

The previous prime is 20499971. The next prime is 20500019. The reversal of 20499999 is 99999402.

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

It is not a de Polignac number, because 20499999 - 2⁵ = 20499967 is a prime.

20499999 is a modest number, since divided by 9999 gives 2049 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20499929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 262782 + ... + 262859.

It is an arithmetic number, because the mean of its divisors is an integer number (3679494).

Almost surely, 2^20499999 is an apocalyptic number.

20499999 is a deficient number, since it is larger than the sum of its proper divisors (8935953).

20499999 is a wasteful number, since it uses less digits than its factorization.

20499999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525657.

The product of its (nonzero) digits is 472392, while the sum is 51.

The square root of 20499999 is about 4527.6924586372. The cubic root of 20499999 is about 273.6851792898.

The spelling of 20499999 in words is "twenty million, four hundred ninety-nine thousand, nine hundred ninety-nine".