1057281621 has 8 divisors (see below), whose sum is σ = 1537864224. Its totient is φ = 640776720.

The previous prime is 1057281613. The next prime is 1057281649. The reversal of 1057281621 is 1261827501.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1057281621 - 2³ = 1057281613 is a prime.

It is a super-2 number, since 2×1057281621² = 2235688852208775282, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 32038837 = 1057281621 / (1 + 0 + 5 + 7 + 2 + 8 + 1 + 6 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1057281601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16019386 + ... + 16019451.

It is an arithmetic number, because the mean of its divisors is an integer number (192233028).

Almost surely, 2^1057281621 is an apocalyptic number.

1057281621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1057281621 is a deficient number, since it is larger than the sum of its proper divisors (480582603).

1057281621 is a wasteful number, since it uses less digits than its factorization.

1057281621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32038851.

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 1057281621 is about 32515.8672189440. The cubic root of 1057281621 is about 1018.7404743686.

The spelling of 1057281621 in words is "one billion, fifty-seven million, two hundred eighty-one thousand, six hundred twenty-one".