20431099 has 16 divisors (see below), whose sum is σ = 23339680. Its totient is φ = 17729280.

The previous prime is 20431097. The next prime is 20431121. The reversal of 20431099 is 99013402.

It is a happy number.

It is not a de Polignac number, because 20431099 - 2¹ = 20431097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20431091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44479 + ... + 44935.

It is an arithmetic number, because the mean of its divisors is an integer number (1458730).

Almost surely, 2^20431099 is an apocalyptic number.

20431099 is a deficient number, since it is larger than the sum of its proper divisors (2908581).

20431099 is a wasteful number, since it uses less digits than its factorization.

20431099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 670.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 20431099 is about 4520.0773223475. The cubic root of 20431099 is about 273.3782187177.

The spelling of 20431099 in words is "twenty million, four hundred thirty-one thousand, ninety-nine".