81906652 has 18 divisors (see below), whose sum is σ = 145751424. Its totient is φ = 40274640.

The previous prime is 81906637. The next prime is 81906667. The reversal of 81906652 is 25660918.

It is an interprime number because it is at equal distance from previous prime (81906637) and next prime (81906667).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12133 + ... + 17635.

Almost surely, 2^81906652 is an apocalyptic number.

It is an amenable number.

81906652 is a deficient number, since it is larger than the sum of its proper divisors (63844772).

81906652 is a wasteful number, since it uses less digits than its factorization.

81906652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5629 (or 5566 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 81906652 is about 9050.2293893580. The cubic root of 81906652 is about 434.2832288021.

The spelling of 81906652 in words is "eighty-one million, nine hundred six thousand, six hundred fifty-two".