1634357021 has 4 divisors (see below), whose sum is σ = 1782934944. Its totient is φ = 1485779100.

The previous prime is 1634357017. The next prime is 1634357083. The reversal of 1634357021 is 1207534361.

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.

It is a cyclic number.

It is not a de Polignac number, because 1634357021 - 2² = 1634357017 is a prime.

It is a super-2 number, since 2×1634357021² = 5342245744183988882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1634377021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74288945 + ... + 74288966.

It is an arithmetic number, because the mean of its divisors is an integer number (445733736).

Almost surely, 2^1634357021 is an apocalyptic number.

1634357021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1634357021 is a deficient number, since it is larger than the sum of its proper divisors (148577923).

1634357021 is a wasteful number, since it uses less digits than its factorization.

1634357021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148577922.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 1634357021 is about 40427.1817098348. The cubic root of 1634357021 is about 1177.9195893182.

The spelling of 1634357021 in words is "one billion, six hundred thirty-four million, three hundred fifty-seven thousand, twenty-one".