81361502 has 4 divisors (see below), whose sum is σ = 122042256. Its totient is φ = 40680750.

The previous prime is 81361499. The next prime is 81361513. The reversal of 81361502 is 20516318.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20340374 + ... + 20340377.

It is an arithmetic number, because the mean of its divisors is an integer number (30510564).

Almost surely, 2^81361502 is an apocalyptic number.

81361502 is a deficient number, since it is larger than the sum of its proper divisors (40680754).

81361502 is a wasteful number, since it uses less digits than its factorization.

81361502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40680753.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 81361502 is about 9020.0610862677. The cubic root of 81361502 is about 433.3175900921.

The spelling of 81361502 in words is "eighty-one million, three hundred sixty-one thousand, five hundred two".