90420637 has 16 divisors (see below), whose sum is σ = 101738160. Its totient is φ = 79930368.

The previous prime is 90420599. The next prime is 90420641. The reversal of 90420637 is 73602409.

It can be written as a sum of positive squares in 8 ways, for example, as 27154521 + 63266116 = 5211^2 + 7954^2 .

It is a cyclic number.

It is not a de Polignac number, because 90420637 - 2¹⁹ = 89896349 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 90420599 and 90420608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90420667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15763 + ... + 20719.

It is an arithmetic number, because the mean of its divisors is an integer number (6358635).

Almost surely, 2^90420637 is an apocalyptic number.

It is an amenable number.

90420637 is a deficient number, since it is larger than the sum of its proper divisors (11317523).

90420637 is a wasteful number, since it uses less digits than its factorization.

90420637 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5040.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 90420637 is about 9508.9766536678. The cubic root of 90420637 is about 448.8375544746.

The spelling of 90420637 in words is "ninety million, four hundred twenty thousand, six hundred thirty-seven".