20561662 has 16 divisors (see below), whose sum is σ = 33866352. Its totient is φ = 9285120.

The previous prime is 20561647. The next prime is 20561663. The reversal of 20561662 is 26616502.

It is a self number, because there is not a number n which added to its sum of digits gives 20561662.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20561663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 478 + ... + 6430.

It is an arithmetic number, because the mean of its divisors is an integer number (2116647).

Almost surely, 2^20561662 is an apocalyptic number.

20561662 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20561662 is a deficient number, since it is larger than the sum of its proper divisors (13304690).

20561662 is a wasteful number, since it uses less digits than its factorization.

20561662 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6123.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 20561662 is about 4534.4968849918. The cubic root of 20561662 is about 273.9593151804.

The spelling of 20561662 in words is "twenty million, five hundred sixty-one thousand, six hundred sixty-two".