81087602 has 4 divisors (see below), whose sum is σ = 121631406. Its totient is φ = 40543800.

The previous prime is 81087563. The next prime is 81087619. The reversal of 81087602 is 20678018.

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., 54037201 + 27050401 = 7351^2 + 5201^2 .

It is a super-2 number, since 2×81087602² = 13150398396220808, which contains 22 as substring.

It is an unprimeable number.

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, 20271899 + ... + 20271902.

Almost surely, 2^81087602 is an apocalyptic number.

81087602 is a deficient number, since it is larger than the sum of its proper divisors (40543804).

81087602 is a wasteful number, since it uses less digits than its factorization.

81087602 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40543803.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 81087602 is about 9004.8654626263. The cubic root of 81087602 is about 432.8307950761.

The spelling of 81087602 in words is "eighty-one million, eighty-seven thousand, six hundred two".