90709690 has 16 divisors (see below), whose sum is σ = 165113640. Its totient is φ = 35875840.

The previous prime is 90709679. The next prime is 90709693. The reversal of 90709690 is 9690709.

It can be written as a sum of positive squares in 4 ways, for example, as 28504921 + 62204769 = 5339^2 + 7887^2 .

It is a super-2 number, since 2×90709690² = 16456495719792200, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (90709693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50071 + ... + 51850.

Almost surely, 2^90709690 is an apocalyptic number.

90709690 is a deficient number, since it is larger than the sum of its proper divisors (74403950).

90709690 is a wasteful number, since it uses less digits than its factorization.

90709690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102017.

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 90709690 is about 9524.1634803273. The cubic root of 90709690 is about 449.3153209228.

The spelling of 90709690 in words is "ninety million, seven hundred nine thousand, six hundred ninety".