81430690 has 16 divisors (see below), whose sum is σ = 159900480. Its totient is φ = 29611120.

The previous prime is 81430621. The next prime is 81430693. The reversal of 81430690 is 9603418.

It is a super-2 number, since 2×81430690² = 13261914547752200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81430693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 370030 + ... + 370249.

It is an arithmetic number, because the mean of its divisors is an integer number (9993780).

Almost surely, 2^81430690 is an apocalyptic number.

81430690 is a deficient number, since it is larger than the sum of its proper divisors (78469790).

81430690 is a wasteful number, since it uses less digits than its factorization.

81430690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740297.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 81430690 is about 9023.8955002815. The cubic root of 81430690 is about 433.4403831514.

The spelling of 81430690 in words is "eighty-one million, four hundred thirty thousand, six hundred ninety".