81253922 has 4 divisors (see below), whose sum is σ = 121880886. Its totient is φ = 40626960.

The previous prime is 81253903. The next prime is 81253927. The reversal of 81253922 is 22935218.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 75498721 + 5755201 = 8689^2 + 2399^2 .

It is not an unprimeable number, because it can be changed into a prime (81253927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20313479 + ... + 20313482.

Almost surely, 2^81253922 is an apocalyptic number.

81253922 is a deficient number, since it is larger than the sum of its proper divisors (40626964).

81253922 is a wasteful number, since it uses less digits than its factorization.

81253922 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40626963.

The product of its digits is 8640, while the sum is 32.

The square root of 81253922 is about 9014.0957394516. The cubic root of 81253922 is about 433.1265215630.

The spelling of 81253922 in words is "eighty-one million, two hundred fifty-three thousand, nine hundred twenty-two".