81722050 has 12 divisors (see below), whose sum is σ = 152003106. Its totient is φ = 32688800.

The previous prime is 81722027. The next prime is 81722057. The reversal of 81722050 is 5022718.

It can be written as a sum of positive squares in 3 ways, for example, as 36469521 + 45252529 = 6039^2 + 6727^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (81722057) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 817171 + ... + 817270.

Almost surely, 2^81722050 is an apocalyptic number.

81722050 is a deficient number, since it is larger than the sum of its proper divisors (70281056).

81722050 is a wasteful number, since it uses less digits than its factorization.

81722050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1634453 (or 1634448 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 81722050 is about 9040.0248893463. The cubic root of 81722050 is about 433.9567194765.

Adding to 81722050 its reverse (5022718), we get a palindrome (86744768).

The spelling of 81722050 in words is "eighty-one million, seven hundred twenty-two thousand, fifty".