1551135231 has 16 divisors (see below), whose sum is σ = 2299137120. Its totient is φ = 1033568640.

The previous prime is 1551135163. The next prime is 1551135277. The reversal of 1551135231 is 1325311551.

It is not a de Polignac number, because 1551135231 - 2⁹ = 1551134719 is a prime.

It is a super-2 number, since 2×1551135231² = 4812041009698846722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 1551135195 and 1551135204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1551135331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44391 + ... + 71223.

It is an arithmetic number, because the mean of its divisors is an integer number (143696070).

Almost surely, 2^1551135231 is an apocalyptic number.

1551135231 is a deficient number, since it is larger than the sum of its proper divisors (748001889).

1551135231 is a wasteful number, since it uses less digits than its factorization.

1551135231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28983 (or 28977 counting only the distinct ones).

The product of its digits is 2250, while the sum is 27.

The square root of 1551135231 is about 39384.4541792825. The cubic root of 1551135231 is about 1157.5769952219.

Adding to 1551135231 its reverse (1325311551), we get a palindrome (2876446782).

The spelling of 1551135231 in words is "one billion, five hundred fifty-one million, one hundred thirty-five thousand, two hundred thirty-one".