36640921 has 4 divisors (see below), whose sum is σ = 37534644. Its totient is φ = 35747200.

The previous prime is 36640883. The next prime is 36640957. The reversal of 36640921 is 12904663.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12904663 = 251 ⋅51413.

It can be written as a sum of positive squares in 2 ways, for example, as 9486400 + 27154521 = 3080^2 + 5211^2 .

It is a cyclic number.

It is not a de Polignac number, because 36640921 - 2¹¹ = 36638873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (36640991) 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, 446800 + ... + 446881.

It is an arithmetic number, because the mean of its divisors is an integer number (9383661).

Almost surely, 2^36640921 is an apocalyptic number.

It is an amenable number.

36640921 is a deficient number, since it is larger than the sum of its proper divisors (893723).

36640921 is an equidigital number, since it uses as much as digits as its factorization.

36640921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 893722.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 36640921 is about 6053.1744564319. The cubic root of 36640921 is about 332.1407233554.

The spelling of 36640921 in words is "thirty-six million, six hundred forty thousand, nine hundred twenty-one".