20988459 has 12 divisors (see below), whose sum is σ = 30683016. Its totient is φ = 13823232.

The previous prime is 20988437. The next prime is 20988467. The reversal of 20988459 is 95488902.

It is not a de Polignac number, because 20988459 - 2⁸ = 20988203 is a prime.

It is a super-2 number, since 2×20988459² = 881030822389362, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20981459) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13302 + ... + 14795.

It is an arithmetic number, because the mean of its divisors is an integer number (2556918).

Almost surely, 2^20988459 is an apocalyptic number.

20988459 is a deficient number, since it is larger than the sum of its proper divisors (9694557).

20988459 is a wasteful number, since it uses less digits than its factorization.

20988459 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28186 (or 28183 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 20988459 is about 4581.3162955640. The cubic root of 20988459 is about 275.8418675133.

The spelling of 20988459 in words is "twenty million, nine hundred eighty-eight thousand, four hundred fifty-nine".