1541739721 has 2 divisors, whose sum is σ = 1541739722. Its totient is φ = 1541739720.

The previous prime is 1541739583. The next prime is 1541739733. The reversal of 1541739721 is 1279371451.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1541426121 + 313600 = 39261^2 + 560^2 .

It is a cyclic number.

It is not a de Polignac number, because 1541739721 - 2²¹ = 1539642569 is a prime.

It is a super-2 number, since 2×1541739721² = 4753922734618315682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1541739761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 770869860 + 770869861.

It is an arithmetic number, because the mean of its divisors is an integer number (770869861).

Almost surely, 2^1541739721 is an apocalyptic number.

It is an amenable number.

1541739721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1541739721 is an equidigital number, since it uses as much as digits as its factorization.

1541739721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 52920, while the sum is 40.

The square root of 1541739721 is about 39264.9935820700. The cubic root of 1541739721 is about 1155.2350417132.

The spelling of 1541739721 in words is "one billion, five hundred forty-one million, seven hundred thirty-nine thousand, seven hundred twenty-one".