20251242 has 64 divisors (see below), whose sum is σ = 49720320. Its totient is φ = 6058800.

The previous prime is 20251241. The next prime is 20251249. The reversal of 20251242 is 24215202.

It is a super-2 number, since 2×20251242² = 820225605085128, which contains 22 as substring.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20251241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 61017 + ... + 61347.

It is an arithmetic number, because the mean of its divisors is an integer number (776880).

Almost surely, 2^20251242 is an apocalyptic number.

20251242 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 20251242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24860160).

20251242 is an abundant number, since it is smaller than the sum of its proper divisors (29469078).

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

20251242 is a wasteful number, since it uses less digits than its factorization.

20251242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456 (or 450 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 20251242 is about 4500.1379978841. The cubic root of 20251242 is about 272.5736613140.

Adding to 20251242 its reverse (24215202), we get a palindrome (44466444).

The spelling of 20251242 in words is "twenty million, two hundred fifty-one thousand, two hundred forty-two".