19902481 has 4 divisors (see below), whose sum is σ = 20950000. Its totient is φ = 18854964.

The previous prime is 19902469. The next prime is 19902499. The reversal of 19902481 is 18420991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19902481 - 2¹³ = 19894289 is a prime.

It is a super-2 number, since 2×19902481² = 792217499910722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19902451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 523731 + ... + 523768.

It is an arithmetic number, because the mean of its divisors is an integer number (5237500).

Almost surely, 2^19902481 is an apocalyptic number.

It is an amenable number.

19902481 is a deficient number, since it is larger than the sum of its proper divisors (1047519).

19902481 is a wasteful number, since it uses less digits than its factorization.

19902481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1047518.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 19902481 is about 4461.2196762769. The cubic root of 19902481 is about 270.9998638362. Note that the first 3 decimals are identical.

It can be divided in two parts, 19 and 902481, that added together give a square (902500 = 950²).

The spelling of 19902481 in words is "nineteen million, nine hundred two thousand, four hundred eighty-one".