20269861 has 6 divisors (see below), whose sum is σ = 20564486. Its totient is φ = 19979400.

The previous prime is 20269853. The next prime is 20269871. The reversal of 20269861 is 16896202.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 12602500 + 7667361 = 3550^2 + 2769^2 .

It is not a de Polignac number, because 20269861 - 2³ = 20269853 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 (20269841) 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, 3031 + ... + 7051.

Almost surely, 2^20269861 is an apocalyptic number.

It is an amenable number.

20269861 is a deficient number, since it is larger than the sum of its proper divisors (294625).

20269861 is an frugal number, since it uses more digits than its factorization.

20269861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4163 (or 4092 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 20269861 is about 4502.2062369465. The cubic root of 20269861 is about 272.6571705042.

The spelling of 20269861 in words is "twenty million, two hundred sixty-nine thousand, eight hundred sixty-one".