20948391 has 6 divisors (see below), whose sum is σ = 30258800. Its totient is φ = 13965588.

The previous prime is 20948387. The next prime is 20948399. The reversal of 20948391 is 19384902.

It is not a de Polignac number, because 20948391 - 2² = 20948387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20948399) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1163791 + ... + 1163808.

Almost surely, 2^20948391 is an apocalyptic number.

20948391 is a deficient number, since it is larger than the sum of its proper divisors (9310409).

20948391 is a wasteful number, since it uses less digits than its factorization.

20948391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2327605 (or 2327602 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 20948391 is about 4576.9412275012. The cubic root of 20948391 is about 275.6662238000. Note that the first 3 decimals are identical.

The spelling of 20948391 in words is "twenty million, nine hundred forty-eight thousand, three hundred ninety-one".