1011121231 has 4 divisors (see below), whose sum is σ = 1012490200. Its totient is φ = 1009752264.

The previous prime is 1011121219. The next prime is 1011121261. The reversal of 1011121231 is 1321211101.

It is a happy number.

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 1011121231 - 2⁷ = 1011121103 is a prime.

It is a super-2 number, since 2×1011121231² = 2044732287557910722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011121261) 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, 683376 + ... + 684853.

It is an arithmetic number, because the mean of its divisors is an integer number (253122550).

Almost surely, 2^1011121231 is an apocalyptic number.

1011121231 is a deficient number, since it is larger than the sum of its proper divisors (1368969).

1011121231 is an equidigital number, since it uses as much as digits as its factorization.

1011121231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1368968.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1011121231 is about 31798.1325080578. The cubic root of 1011121231 is about 1003.6934188627.

Adding to 1011121231 its reverse (1321211101), we get a palindrome (2332332332).

The spelling of 1011121231 in words is "one billion, eleven million, one hundred twenty-one thousand, two hundred thirty-one".