1372724021 has 2 divisors, whose sum is σ = 1372724022. Its totient is φ = 1372724020.

The previous prime is 1372723991. The next prime is 1372724069. The reversal of 1372724021 is 1204272731.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1362643396 + 10080625 = 36914^2 + 3175^2 .

It is a cyclic number.

It is not a de Polignac number, because 1372724021 - 2²² = 1368529717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1372724071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 686362010 + 686362011.

It is an arithmetic number, because the mean of its divisors is an integer number (686362011).

Almost surely, 2^1372724021 is an apocalyptic number.

It is an amenable number.

1372724021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1372724021 is an equidigital number, since it uses as much as digits as its factorization.

1372724021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 1372724021 is about 37050.2904307105. The cubic root of 1372724021 is about 1111.3761631784.

Adding to 1372724021 its reverse (1204272731), we get a palindrome (2576996752).

The spelling of 1372724021 in words is "one billion, three hundred seventy-two million, seven hundred twenty-four thousand, twenty-one".