81146554 has 4 divisors (see below), whose sum is σ = 121719834. Its totient is φ = 40573276.

The previous prime is 81146537. The next prime is 81146563. The reversal of 81146554 is 45564118.

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., 80192025 + 954529 = 8955^2 + 977^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20286637 + ... + 20286640.

Almost surely, 2^81146554 is an apocalyptic number.

81146554 is a deficient number, since it is larger than the sum of its proper divisors (40573280).

81146554 is a wasteful number, since it uses less digits than its factorization.

81146554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40573279.

The product of its digits is 19200, while the sum is 34.

The square root of 81146554 is about 9008.1382094193. The cubic root of 81146554 is about 432.9356613332.

The spelling of 81146554 in words is "eighty-one million, one hundred forty-six thousand, five hundred fifty-four".