19945431 has 48 divisors (see below), whose sum is σ = 33266688. Its totient is φ = 11404800.

The previous prime is 19945427. The next prime is 19945447. The reversal of 19945431 is 13454991.

It is a happy number.

It is not a de Polignac number, because 19945431 - 2² = 19945427 is a prime.

It is a super-2 number, since 2×19945431² = 795640435551522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19945451) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 205575 + ... + 205671.

It is an arithmetic number, because the mean of its divisors is an integer number (693056).

Almost surely, 2^19945431 is an apocalyptic number.

19945431 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

19945431 is a deficient number, since it is larger than the sum of its proper divisors (13321257).

19945431 is a wasteful number, since it uses less digits than its factorization.

19945431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 209 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 19945431 is about 4466.0307880712. The cubic root of 19945431 is about 271.1946650346.

The spelling of 19945431 in words is "nineteen million, nine hundred forty-five thousand, four hundred thirty-one".