20051690 has 16 divisors (see below), whose sum is σ = 36312192. Its totient is φ = 7971984.

The previous prime is 20051683. The next prime is 20051711. The reversal of 20051690 is 9615002.

It is a super-2 number, since 2×20051690² = 804140543712200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4334 + ... + 7673.

It is an arithmetic number, because the mean of its divisors is an integer number (2269512).

Almost surely, 2^20051690 is an apocalyptic number.

20051690 is a deficient number, since it is larger than the sum of its proper divisors (16260502).

20051690 is a wasteful number, since it uses less digits than its factorization.

20051690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12181.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 20051690 is about 4477.9113434725. The cubic root of 20051690 is about 271.6754075667.

Adding to 20051690 its reverse (9615002), we get a palindrome (29666692).

The spelling of 20051690 in words is "twenty million, fifty-one thousand, six hundred ninety".