90212690 has 8 divisors (see below), whose sum is σ = 162382860. Its totient is φ = 36085072.

The previous prime is 90212687. The next prime is 90212699. The reversal of 90212690 is 9621209.

It can be written as a sum of positive squares in 2 ways, for example, as 89170249 + 1042441 = 9443^2 + 1021^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×90212690² = 16276658874072200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (90212699) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4510625 + ... + 4510644.

Almost surely, 2^90212690 is an apocalyptic number.

90212690 is a deficient number, since it is larger than the sum of its proper divisors (72170170).

90212690 is a wasteful number, since it uses less digits than its factorization.

90212690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9021276.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 90212690 is about 9498.0361127972. The cubic root of 90212690 is about 448.4932154426.

Adding to 90212690 its reverse (9621209), we get a palindrome (99833899).

It can be divided in two parts, 9021 and 2690, that added together give a palindrome (11711).

The spelling of 90212690 in words is "ninety million, two hundred twelve thousand, six hundred ninety".