1245223021 has 32 divisors (see below), whose sum is σ = 1537643520. Its totient is φ = 984220416.

The previous prime is 1245223009. The next prime is 1245223039. The reversal of 1245223021 is 1203225421.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1245223021 - 2¹⁷ = 1245091949 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1245222983 and 1245223001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1245223051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1372450 + ... + 1373356.

It is an arithmetic number, because the mean of its divisors is an integer number (48051360).

Almost surely, 2^1245223021 is an apocalyptic number.

It is an amenable number.

1245223021 is a deficient number, since it is larger than the sum of its proper divisors (292420499).

1245223021 is a wasteful number, since it uses less digits than its factorization.

1245223021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1153.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 1245223021 is about 35287.7177074404. The cubic root of 1245223021 is about 1075.8433680348.

Adding to 1245223021 its reverse (1203225421), we get a palindrome (2448448442).

The spelling of 1245223021 in words is "one billion, two hundred forty-five million, two hundred twenty-three thousand, twenty-one".