20899761 has 16 divisors (see below), whose sum is σ = 28319808. Its totient is φ = 13708800.

The previous prime is 20899757. The next prime is 20899789. The reversal of 20899761 is 16799802.

It is not a de Polignac number, because 20899761 - 2² = 20899757 is a prime.

It is a super-4 number, since 4×20899761⁴ (a number of 30 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (20899721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86601 + ... + 86841.

It is an arithmetic number, because the mean of its divisors is an integer number (1769988).

Almost surely, 2^20899761 is an apocalyptic number.

It is an amenable number.

20899761 is a deficient number, since it is larger than the sum of its proper divisors (7420047).

20899761 is a wasteful number, since it uses less digits than its factorization.

20899761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 592.

The product of its (nonzero) digits is 54432, while the sum is 42.

The square root of 20899761 is about 4571.6256408416. The cubic root of 20899761 is about 275.4527462233.

The spelling of 20899761 in words is "twenty million, eight hundred ninety-nine thousand, seven hundred sixty-one".