1621204634 has 16 divisors (see below), whose sum is σ = 2900043648. Its totient is φ = 664593072.

The previous prime is 1621204601. The next prime is 1621204639. The reversal of 1621204634 is 4364021261.

It is a junction number, because it is equal to n+sod(n) for n = 1621204597 and 1621204606.

It is not an unprimeable number, because it can be changed into a prime (1621204639) 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, 2517077 + ... + 2517720.

It is an arithmetic number, because the mean of its divisors is an integer number (181252728).

Almost surely, 2^1621204634 is an apocalyptic number.

1621204634 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1621204634 is a deficient number, since it is larger than the sum of its proper divisors (1278839014).

1621204634 is a wasteful number, since it uses less digits than its factorization.

1621204634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5034829.

The product of its (nonzero) digits is 6912, while the sum is 29.

The square root of 1621204634 is about 40264.1855002681. The cubic root of 1621204634 is about 1174.7513302650.

Adding to 1621204634 its reverse (4364021261), we get a palindrome (5985225895).

The spelling of 1621204634 in words is "one billion, six hundred twenty-one million, two hundred four thousand, six hundred thirty-four".