20490401 has 4 divisors (see below), whose sum is σ = 21381312. Its totient is φ = 19599492.

The previous prime is 20490397. The next prime is 20490413. The reversal of 20490401 is 10409402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10409402 = 2 ⋅5204701.

It is a cyclic number.

It is not a de Polignac number, because 20490401 - 2² = 20490397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20490451) 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, 445421 + ... + 445466.

It is an arithmetic number, because the mean of its divisors is an integer number (5345328).

Almost surely, 2^20490401 is an apocalyptic number.

It is an amenable number.

20490401 is a deficient number, since it is larger than the sum of its proper divisors (890911).

20490401 is an equidigital number, since it uses as much as digits as its factorization.

20490401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890910.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 20490401 is about 4526.6324127324. The cubic root of 20490401 is about 273.6424599313.

Adding to 20490401 its reverse (10409402), we get a palindrome (30899803).

The spelling of 20490401 in words is "twenty million, four hundred ninety thousand, four hundred one".