20390451 has 16 divisors (see below), whose sum is σ = 28277760. Its totient is φ = 13053600.

The previous prime is 20390431. The next prime is 20390483. The reversal of 20390451 is 15409302.

It is not a de Polignac number, because 20390451 - 2⁷ = 20390323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20390411) 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, 18876 + ... + 19926.

It is an arithmetic number, because the mean of its divisors is an integer number (1767360).

Almost surely, 2^20390451 is an apocalyptic number.

20390451 is a deficient number, since it is larger than the sum of its proper divisors (7887309).

20390451 is a wasteful number, since it uses less digits than its factorization.

20390451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1306.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 20390451 is about 4515.5787004547. The cubic root of 20390451 is about 273.1968015663.

Adding to 20390451 its reverse (15409302), we get a palindrome (35799753).

The spelling of 20390451 in words is "twenty million, three hundred ninety thousand, four hundred fifty-one".