20249691 has 32 divisors (see below), whose sum is σ = 34368000. Its totient is φ = 10513440.

The previous prime is 20249681. The next prime is 20249699. The reversal of 20249691 is 19694202.

It is not a de Polignac number, because 20249691 - 2⁷ = 20249563 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (20249699) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10425 + ... + 12213.

It is an arithmetic number, because the mean of its divisors is an integer number (1074000).

Almost surely, 2^20249691 is an apocalyptic number.

20249691 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20249691 is a deficient number, since it is larger than the sum of its proper divisors (14118309).

20249691 is a wasteful number, since it uses less digits than its factorization.

20249691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1824 (or 1810 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 20249691 is about 4499.9656665357. The cubic root of 20249691 is about 272.5667025221.

The spelling of 20249691 in words is "twenty million, two hundred forty-nine thousand, six hundred ninety-one".