25221768 has 64 divisors (see below), whose sum is σ = 74088000. Its totient is φ = 7054080.

The previous prime is 25221767. The next prime is 25221769. The reversal of 25221768 is 86712252.

It is an interprime number because it is at equal distance from previous prime (25221767) and next prime (25221769).

It is a super-2 number, since 2×25221768² = 1272275162091648, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (25221767) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 243 + ... + 7106.

It is an arithmetic number, because the mean of its divisors is an integer number (1157625).

Almost surely, 2^25221768 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 25221768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37044000).

25221768 is an abundant number, since it is smaller than the sum of its proper divisors (48866232).

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

25221768 is a wasteful number, since it uses less digits than its factorization.

25221768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7382 (or 7378 counting only the distinct ones).

The product of its digits is 13440, while the sum is 33.

The square root of 25221768 is about 5022.1278358879. The cubic root of 25221768 is about 293.2638345452.

The spelling of 25221768 in words is "twenty-five million, two hundred twenty-one thousand, seven hundred sixty-eight".