37212821 has 4 divisors (see below), whose sum is σ = 37542252. Its totient is φ = 36883392.

The previous prime is 37212817. The next prime is 37212839. The reversal of 37212821 is 12821273.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1380625 + 35832196 = 1175^2 + 5986^2 .

It is a cyclic number.

It is not a de Polignac number, because 37212821 - 2² = 37212817 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 (37212521) 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, 164546 + ... + 164771.

It is an arithmetic number, because the mean of its divisors is an integer number (9385563).

Almost surely, 2^37212821 is an apocalyptic number.

It is an amenable number.

37212821 is a deficient number, since it is larger than the sum of its proper divisors (329431).

37212821 is a wasteful number, since it uses less digits than its factorization.

37212821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 329430.

The product of its digits is 1344, while the sum is 26.

The square root of 37212821 is about 6100.2312251258. The cubic root of 37212821 is about 333.8598531151.

The spelling of 37212821 in words is "thirty-seven million, two hundred twelve thousand, eight hundred twenty-one".