20697451 has 2 divisors, whose sum is σ = 20697452. Its totient is φ = 20697450.

The previous prime is 20697433. The next prime is 20697463. The reversal of 20697451 is 15479602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20697451 - 2⁷ = 20697323 is a prime.

It is not a weakly prime, because it can be changed into another prime (20697421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10348725 + 10348726.

It is an arithmetic number, because the mean of its divisors is an integer number (10348726).

Almost surely, 2^20697451 is an apocalyptic number.

20697451 is a deficient number, since it is larger than the sum of its proper divisors (1).

20697451 is an equidigital number, since it uses as much as digits as its factorization.

20697451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 20697451 is about 4549.4451310022. The cubic root of 20697451 is about 274.5610672770.

It can be divided in two parts, 206974 and 51, that added together give a square (207025 = 455²).

The spelling of 20697451 in words is "twenty million, six hundred ninety-seven thousand, four hundred fifty-one".