81613354 has 4 divisors (see below), whose sum is σ = 122420034. Its totient is φ = 40806676.

The previous prime is 81613351. The next prime is 81613369. The reversal of 81613354 is 45331618.

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., 73359225 + 8254129 = 8565^2 + 2873^2 .

It is a super-2 number, since 2×81613354² = 13321479102258632, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81613351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20403337 + ... + 20403340.

Almost surely, 2^81613354 is an apocalyptic number.

81613354 is a deficient number, since it is larger than the sum of its proper divisors (40806680).

81613354 is a wasteful number, since it uses less digits than its factorization.

81613354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40806679.

The product of its digits is 8640, while the sum is 31.

The square root of 81613354 is about 9034.0109585942. The cubic root of 81613354 is about 433.7642365914.

The spelling of 81613354 in words is "eighty-one million, six hundred thirteen thousand, three hundred fifty-four".