20690998 has 16 divisors (see below), whose sum is σ = 32440320. Its totient is φ = 9887976.

The previous prime is 20690993. The next prime is 20691001. The reversal of 20690998 is 89909602.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20690993) 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, 1483 + ... + 6601.

It is an arithmetic number, because the mean of its divisors is an integer number (2027520).

Almost surely, 2^20690998 is an apocalyptic number.

20690998 is a deficient number, since it is larger than the sum of its proper divisors (11749322).

20690998 is a wasteful number, since it uses less digits than its factorization.

20690998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5211.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 20690998 is about 4548.7358683485. The cubic root of 20690998 is about 274.5325303213.

It can be divided in two parts, 206 and 90998, that added together give a square (91204 = 302²).

The spelling of 20690998 in words is "twenty million, six hundred ninety thousand, nine hundred ninety-eight".