20249899 has 4 divisors (see below), whose sum is σ = 20270536. Its totient is φ = 20229264.

The previous prime is 20249893. The next prime is 20249963. The reversal of 20249899 is 99894202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99894202 = 2 ⋅49947101.

It is a cyclic number.

It is not a de Polignac number, because 20249899 - 2³ = 20249891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20249891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8769 + ... + 10834.

It is an arithmetic number, because the mean of its divisors is an integer number (5067634).

Almost surely, 2^20249899 is an apocalyptic number.

20249899 is a deficient number, since it is larger than the sum of its proper divisors (20637).

20249899 is a wasteful number, since it uses less digits than its factorization.

20249899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20636.

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 20249899 is about 4499.9887777638. The cubic root of 20249899 is about 272.5676357656.

The spelling of 20249899 in words is "twenty million, two hundred forty-nine thousand, eight hundred ninety-nine".