20761406 has 4 divisors (see below), whose sum is σ = 31142112. Its totient is φ = 10380702.

The previous prime is 20761399. The next prime is 20761409. The reversal of 20761406 is 60416702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60416702 = 2 ⋅30208351.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20761409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5190350 + ... + 5190353.

It is an arithmetic number, because the mean of its divisors is an integer number (7785528).

Almost surely, 2^20761406 is an apocalyptic number.

20761406 is a deficient number, since it is larger than the sum of its proper divisors (10380706).

20761406 is a wasteful number, since it uses less digits than its factorization.

20761406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10380705.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 20761406 is about 4556.4685887209. The cubic root of 20761406 is about 274.8435738481.

The spelling of 20761406 in words is "twenty million, seven hundred sixty-one thousand, four hundred six".