1621212053 has 4 divisors (see below), whose sum is σ = 1673509248. Its totient is φ = 1568914860.

The previous prime is 1621212029. The next prime is 1621212059. The reversal of 1621212053 is 3502121261.

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, and also an emirpimes, since its reverse is a distinct semiprime: 3502121261 = 17 ⋅206007133.

It is a cyclic number.

It is not a de Polignac number, because 1621212053 - 2⁶ = 1621211989 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 (1621212059) 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, 26148551 + ... + 26148612.

It is an arithmetic number, because the mean of its divisors is an integer number (418377312).

Almost surely, 2^1621212053 is an apocalyptic number.

It is an amenable number.

1621212053 is a deficient number, since it is larger than the sum of its proper divisors (52297195).

1621212053 is an equidigital number, since it uses as much as digits as its factorization.

1621212053 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52297194.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 1621212053 is about 40264.2776291839. The cubic root of 1621212053 is about 1174.7531222384.

The spelling of 1621212053 in words is "one billion, six hundred twenty-one million, two hundred twelve thousand, fifty-three".