20756542 has 4 divisors (see below), whose sum is σ = 31134816. Its totient is φ = 10378270.

The previous prime is 20756521. The next prime is 20756579. The reversal of 20756542 is 24565702.

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

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5189134 + ... + 5189137.

It is an arithmetic number, because the mean of its divisors is an integer number (7783704).

Almost surely, 2^20756542 is an apocalyptic number.

20756542 is a deficient number, since it is larger than the sum of its proper divisors (10378274).

20756542 is a wasteful number, since it uses less digits than its factorization.

20756542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10378273.

The product of its (nonzero) digits is 16800, while the sum is 31.

The square root of 20756542 is about 4555.9348107716. The cubic root of 20756542 is about 274.8221086423.

The spelling of 20756542 in words is "twenty million, seven hundred fifty-six thousand, five hundred forty-two".