81902250 has 96 divisors (see below), whose sum is σ = 224499600. Its totient is φ = 21542400.

The previous prime is 81902239. The next prime is 81902251. The reversal of 81902250 is 5220918.

It can be written as a sum of positive squares in 8 ways, for example, as 5322249 + 76580001 = 2307^2 + 8751^2 .

It is not an unprimeable number, because it can be changed into a prime (81902251) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 200046 + ... + 200454.

Almost surely, 2^81902250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81902250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112249800).

81902250 is an abundant number, since it is smaller than the sum of its proper divisors (142597350).

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

81902250 is a wasteful number, since it uses less digits than its factorization.

81902250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521 (or 508 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 81902250 is about 9049.9861878348. The cubic root of 81902250 is about 434.2754486077.

It can be divided in two parts, 8190 and 2250, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 81902250 in words is "eighty-one million, nine hundred two thousand, two hundred fifty".