1621712055 has 32 divisors (see below), whose sum is σ = 2664990720. Its totient is φ = 841788800.

The previous prime is 1621712051. The next prime is 1621712069. The reversal of 1621712055 is 5502171261.

It is not a de Polignac number, because 1621712055 - 2² = 1621712051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621712051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 80314 + ... + 98456.

It is an arithmetic number, because the mean of its divisors is an integer number (83280960).

Almost surely, 2^1621712055 is an apocalyptic number.

1621712055 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1621712055 is a deficient number, since it is larger than the sum of its proper divisors (1043278665).

1621712055 is a wasteful number, since it uses less digits than its factorization.

1621712055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18311.

The product of its (nonzero) digits is 4200, while the sum is 30.

The square root of 1621712055 is about 40270.4861530129. The cubic root of 1621712055 is about 1174.8738793256.

The spelling of 1621712055 in words is "one billion, six hundred twenty-one million, seven hundred twelve thousand, fifty-five".