20743451 has 4 divisors (see below), whose sum is σ = 21963672. Its totient is φ = 19523232.

The previous prime is 20743427. The next prime is 20743453. The reversal of 20743451 is 15434702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20743451 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20743451.

It is not an unprimeable number, because it can be changed into a prime (20743453) 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, 610085 + ... + 610118.

It is an arithmetic number, because the mean of its divisors is an integer number (5490918).

Almost surely, 2^20743451 is an apocalyptic number.

20743451 is a deficient number, since it is larger than the sum of its proper divisors (1220221).

20743451 is a wasteful number, since it uses less digits than its factorization.

20743451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220220.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 20743451 is about 4554.4978867050. The cubic root of 20743451 is about 274.7643203904.

The spelling of 20743451 in words is "twenty million, seven hundred forty-three thousand, four hundred fifty-one".