19931457 has 16 divisors (see below), whose sum is σ = 32708480. Its totient is φ = 10513152.

The previous prime is 19931447. The next prime is 19931459. The reversal of 19931457 is 75413991.

It is a happy number.

It is not a de Polignac number, because 19931457 - 2¹⁰ = 19930433 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (19931459) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36232 + ... + 36777.

It is an arithmetic number, because the mean of its divisors is an integer number (2044280).

Almost surely, 2^19931457 is an apocalyptic number.

It is an amenable number.

19931457 is a deficient number, since it is larger than the sum of its proper divisors (12777023).

19931457 is a wasteful number, since it uses less digits than its factorization.

19931457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73032.

The product of its digits is 34020, while the sum is 39.

The square root of 19931457 is about 4464.4660375010. The cubic root of 19931457 is about 271.1313161967.

The spelling of 19931457 in words is "nineteen million, nine hundred thirty-one thousand, four hundred fifty-seven".