1020231551 has 4 divisors (see below), whose sum is σ = 1021448400. Its totient is φ = 1019014704.

The previous prime is 1020231533. The next prime is 1020231587. The reversal of 1020231551 is 1551320201.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1020231551 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 (1020231851) 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, 607166 + ... + 608843.

It is an arithmetic number, because the mean of its divisors is an integer number (255362100).

Almost surely, 2^1020231551 is an apocalyptic number.

1020231551 is a deficient number, since it is larger than the sum of its proper divisors (1216849).

1020231551 is an equidigital number, since it uses as much as digits as its factorization.

1020231551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1216848.

The product of its (nonzero) digits is 300, while the sum is 20.

The square root of 1020231551 is about 31941.0637111540. The cubic root of 1020231551 is about 1006.6988752005.

Adding to 1020231551 its reverse (1551320201), we get a palindrome (2571551752).

The spelling of 1020231551 in words is "one billion, twenty million, two hundred thirty-one thousand, five hundred fifty-one".