1054155721 has 4 divisors (see below), whose sum is σ = 1054220752. Its totient is φ = 1054090692.

The previous prime is 1054155709. The next prime is 1054155799. The reversal of 1054155721 is 1275514501.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1275514501 = 1723 ⋅740287.

It is a cyclic number.

It is not a de Polignac number, because 1054155721 - 2¹⁹ = 1053631433 is a prime.

It is a super-2 number, since 2×1054155721² = 2222488568234059682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1054159721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13630 + ... + 47896.

It is an arithmetic number, because the mean of its divisors is an integer number (263555188).

Almost surely, 2^1054155721 is an apocalyptic number.

It is an amenable number.

1054155721 is a deficient number, since it is larger than the sum of its proper divisors (65031).

1054155721 is an equidigital number, since it uses as much as digits as its factorization.

1054155721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65030.

The product of its (nonzero) digits is 7000, while the sum is 31.

The square root of 1054155721 is about 32467.7643363383. The cubic root of 1054155721 is about 1017.7354995024.

The spelling of 1054155721 in words is "one billion, fifty-four million, one hundred fifty-five thousand, seven hundred twenty-one".