1621801882 has 4 divisors (see below), whose sum is σ = 2432702826. Its totient is φ = 810900940.

The previous prime is 1621801873. The next prime is 1621801891. The reversal of 1621801882 is 2881081261.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1621801873) and next prime (1621801891).

It can be written as a sum of positive squares in only one way, i.e., 1553226921 + 68574961 = 39411^2 + 8281^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405450469 + ... + 405450472.

Almost surely, 2^1621801882 is an apocalyptic number.

1621801882 is a deficient number, since it is larger than the sum of its proper divisors (810900944).

1621801882 is an equidigital number, since it uses as much as digits as its factorization.

1621801882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 810900943.

The product of its (nonzero) digits is 12288, while the sum is 37.

The square root of 1621801882 is about 40271.6014332681. The cubic root of 1621801882 is about 1174.8955711024.

The spelling of 1621801882 in words is "one billion, six hundred twenty-one million, eight hundred one thousand, eight hundred eighty-two".