145621021 has 16 divisors (see below), whose sum is σ = 180157824. Its totient is φ = 114617664.

The previous prime is 145621019. The next prime is 145621061. The reversal of 145621021 is 120126541.

It is not a de Polignac number, because 145621021 - 2¹ = 145621019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 145620983 and 145621001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145621001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13866 + ... + 21988.

It is an arithmetic number, because the mean of its divisors is an integer number (11259864).

Almost surely, 2^145621021 is an apocalyptic number.

It is an amenable number.

145621021 is a deficient number, since it is larger than the sum of its proper divisors (34536803).

145621021 is a wasteful number, since it uses less digits than its factorization.

145621021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8340.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 145621021 is about 12067.3535209672. The cubic root of 145621021 is about 526.1077393554.

Adding to 145621021 its reverse (120126541), we get a palindrome (265747562).

The spelling of 145621021 in words is "one hundred forty-five million, six hundred twenty-one thousand, twenty-one".