20251251 has 12 divisors (see below), whose sum is σ = 30260880. Its totient is φ = 13035120.

The previous prime is 20251249. The next prime is 20251303. The reversal of 20251251 is 15215202.

It is not a de Polignac number, because 20251251 - 2¹ = 20251249 is a prime.

It is a super-2 number, since 2×20251251² = 820226334130002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20251211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38535 + ... + 39056.

It is an arithmetic number, because the mean of its divisors is an integer number (2521740).

Almost surely, 2^20251251 is an apocalyptic number.

20251251 is a deficient number, since it is larger than the sum of its proper divisors (10009629).

20251251 is a wasteful number, since it uses less digits than its factorization.

20251251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77626 (or 77623 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 20251251 is about 4500.1389978533. The cubic root of 20251251 is about 272.5737016929.

Adding to 20251251 its reverse (15215202), we get a palindrome (35466453).

It can be divided in two parts, 20251 and 251, that added together give a palindrome (20502).

The spelling of 20251251 in words is "twenty million, two hundred fifty-one thousand, two hundred fifty-one".