20672691 has 16 divisors (see below), whose sum is σ = 30643200. Its totient is φ = 12310560.

The previous prime is 20672683. The next prime is 20672747. The reversal of 20672691 is 19627602.

It is not a de Polignac number, because 20672691 - 2³ = 20672683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20672671) 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, 7341 + ... + 9758.

It is an arithmetic number, because the mean of its divisors is an integer number (1915200).

Almost surely, 2^20672691 is an apocalyptic number.

20672691 is a deficient number, since it is larger than the sum of its proper divisors (9970509).

20672691 is a wasteful number, since it uses less digits than its factorization.

20672691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17146.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20672691 is about 4546.7231057103. The cubic root of 20672691 is about 274.4515393830.

The spelling of 20672691 in words is "twenty million, six hundred seventy-two thousand, six hundred ninety-one".