2145431551 has 4 divisors (see below), whose sum is σ = 2195325352. Its totient is φ = 2095537752.

The previous prime is 2145431543. The next prime is 2145431557. The reversal of 2145431551 is 1551345412.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2145431551 - 2³ = 2145431543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2145431557) 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, 24946836 + ... + 24946921.

It is an arithmetic number, because the mean of its divisors is an integer number (548831338).

Almost surely, 2^2145431551 is an apocalyptic number.

2145431551 is a deficient number, since it is larger than the sum of its proper divisors (49893801).

2145431551 is an equidigital number, since it uses as much as digits as its factorization.

2145431551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49893800.

The product of its digits is 12000, while the sum is 31.

The square root of 2145431551 is about 46318.8034279816. The cubic root of 2145431551 is about 1289.7480731122.

Adding to 2145431551 its reverse (1551345412), we get a palindrome (3696776963).

The spelling of 2145431551 in words is "two billion, one hundred forty-five million, four hundred thirty-one thousand, five hundred fifty-one".