1957939621 has 16 divisors (see below), whose sum is σ = 2190198528. Its totient is φ = 1735156800.

The previous prime is 1957939591. The next prime is 1957939649. The reversal of 1957939621 is 1269397591.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1957939621 - 2¹⁹ = 1957415333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1957939651) 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 15 ways as a sum of consecutive naturals, for example, 80836 + ... + 102226.

It is an arithmetic number, because the mean of its divisors is an integer number (136887408).

Almost surely, 2^1957939621 is an apocalyptic number.

1957939621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1957939621 is a deficient number, since it is larger than the sum of its proper divisors (232258907).

1957939621 is a wasteful number, since it uses less digits than its factorization.

1957939621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21612.

The product of its digits is 918540, while the sum is 52.

The square root of 1957939621 is about 44248.6115149391. The cubic root of 1957939621 is about 1251.0262763216.

The spelling of 1957939621 in words is "one billion, nine hundred fifty-seven million, nine hundred thirty-nine thousand, six hundred twenty-one".