20402464 has 48 divisors (see below), whose sum is σ = 42045696. Its totient is φ = 9734400.

The previous prime is 20402443. The next prime is 20402467. The reversal of 20402464 is 46420402.

It is not an unprimeable number, because it can be changed into a prime (20402467) 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, 129874 + ... + 130030.

It is an arithmetic number, because the mean of its divisors is an integer number (875952).

Almost surely, 2^20402464 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20402464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21022848).

20402464 is an abundant number, since it is smaller than the sum of its proper divisors (21643232).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20402464 is a wasteful number, since it uses less digits than its factorization.

20402464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329 (or 321 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 20402464 is about 4516.9086774032. The cubic root of 20402464 is about 273.2504421794.

Adding to 20402464 its reverse (46420402), we get a palindrome (66822866).

The spelling of 20402464 in words is "twenty million, four hundred two thousand, four hundred sixty-four".