20906019 has 24 divisors (see below), whose sum is σ = 31536960. Its totient is φ = 13839336.

The previous prime is 20905993. The next prime is 20906033. The reversal of 20906019 is 91060902.

It is a happy number.

It is not a de Polignac number, because 20906019 - 2⁵ = 20905987 is a prime.

It is a super-2 number, since 2×20906019² = 874123260856722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 20905983 and 20906001.

It is not an unprimeable number, because it can be changed into a prime (20906819) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 54972 + ... + 55350.

It is an arithmetic number, because the mean of its divisors is an integer number (1314040).

Almost surely, 2^20906019 is an apocalyptic number.

20906019 is a deficient number, since it is larger than the sum of its proper divisors (10630941).

20906019 is an equidigital number, since it uses as much as digits as its factorization.

20906019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 621 (or 609 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 20906019 is about 4572.3100288585. The cubic root of 20906019 is about 275.4802363505.

The spelling of 20906019 in words is "twenty million, nine hundred six thousand, nineteen".