19940431 has 4 divisors (see below), whose sum is σ = 22789072. Its totient is φ = 17091792.

The previous prime is 19940423. The next prime is 19940449. The reversal of 19940431 is 13404991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13404991 = 41 ⋅326951.

It is a cyclic number.

It is not a de Polignac number, because 19940431 - 2³ = 19940423 is a prime.

It is a super-2 number, since 2×19940431² = 795241576931522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19940393 and 19940402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19940411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1424310 + ... + 1424323.

It is an arithmetic number, because the mean of its divisors is an integer number (5697268).

Almost surely, 2^19940431 is an apocalyptic number.

19940431 is a deficient number, since it is larger than the sum of its proper divisors (2848641).

19940431 is an equidigital number, since it uses as much as digits as its factorization.

19940431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2848640.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 19940431 is about 4465.4709718013. The cubic root of 19940431 is about 271.1720017548.

The spelling of 19940431 in words is "nineteen million, nine hundred forty thousand, four hundred thirty-one".